PDA

View Full Version : Big Brake Kits - Real Numbers



dandan
06-08-10, 11:44
Here are a few comparison figures I have generated for our common big brake kits. All calculations are based on some assumptions and come with some caveats:

1. Pads sit in 0.5mm from the edge of the disc.
2. The same pad compound is used for every comparison
3. All kits are listed as "improvement" or "reduction" with a percentage based on their comparison to the UK spec setup ("improvement" means it is more powerful than UK spec)
4. Front to rear bias change is calculated relative to the UK spec setup
5. UK spec front pad depth = 58mm - could somebody verify this please?
6. UK spec rear pad depth = 49mm
7. Use at your own risk - I worked these out for my own benefit when looking into buying a BBK off the shelf
8. I am sharing the numbers here for interest's sake - not to start any arguments or for anyone to go away and build their own kit based on my calculations
9. If you have any piston diameters or pad depths for the applications where I have gaps in the data then please let me know.
10. Please let me know if you think there are any mistakes or contradictions.
11. This data relates to actual braking capability based on the dimensions of the disc, pad and caliper. There is no accounting for temperature, heat capacity, feel and pad knock back, rotating mass, unsprung mass, caliper stiffness, pad choice etc. Some of these are subjective whereas others can be quantified (another post coming on that soon).


I'll add more to this list and fill in the gaps as I get the time and extra info (e.g. Brembo's "C" non-monoblock rear caliper that they sell to go with the 14" monoblock front kit). Rear caliper info is generally very hard to come by!

dandan
06-08-10, 11:44
Brembo

Brembo 6 Piston Monoblock - 14" (51.75mm pad depth) with a UK rear setup
Braking torque: 4.6% reduction
Front/rear bias: 1.5% extra to rear


Brembo 6 Piston Monoblock - 14" (48.7mm pad depth) with a UK rear setup
Braking torque: 3.9% reduction
Front/rear bias: 1.3% extra to rear


Brembo 6 Piston Monoblock - 14" (51.75mm pad depth) with Brembo 13.58" rear and Brembo "C" caliper
Braking torque: ??% reduction
Front/rear bias: ...(need rear caliper info)


Brembo 6 Piston Monoblock - 14" (48.7mm pad depth) with Brembo 13.58" rear and Brembo "C" caliper
Braking torque: ??% reduction
Front/rear bias: ...(need rear caliper info)

dandan
06-08-10, 11:44
AP

AP Road Kit CP5555 6 Piston caliper - 356mm (54mm pad depth) with a UK rear setup
Braking torque: 0.5% reduction
Front/rear bias: 0.1% extra to rear


AP Road Kit CP5555 6 piston caliper - 356mm (54mm pad depth) with an AP 330mm rear (44.1mm pad depth)
Braking torque: 2.7% reduction
Front/rear bias: 1.4% extra to front


AP Race Kit Pro5000+ 6 piston caliper - 362mm disc (54mm pad depth) with a UK rear setup
Braking torque: 0.9% improvement
Front/rear bias: 0.3% extra to front


AP Race Kit Pro5000+ 6 piston caliper - 362mm disc (54mm pad depth) with an AP 343mm rear
Braking torque: ??% improvement
Front/rear bias: ...(need rear caliper info)

dandan
06-08-10, 11:44
KAD

KAD 17" Wheel Kit - 6 Piston G caliper on UK front disc (46mm pad depth) with a UK rear setup
Braking torque: 7.8% reduction
Front/rear bias: 2.7% extra to rear


KAD 18" Wheel Kit - 6 Piston H caliper - 356mm disc (46mm pad depth) with a UK rear setup
Braking torque: 0.6% reduction
Front/rear bias: 0.2% extra to rear


KAD 18" Wheel Kit - 6 Piston H caliper - 356mm disc (46mm pad depth) with a UK rear disc and KAD rear caliper (49mm pad depth - can someone confirm this please?)
Braking torque: 5.1% improvement
Front/rear bias: 3.9% extra to rear


KAD 19" Wheel Kit - 6 Piston H caliper - 378mm disc (46mm pad depth) with a UK rear setup
Braking torque: 4.3% improvement
Front/rear bias: 1.3% extra to front


KAD 19" Wheel Kit - 6 Piston H caliper - 378mm disc (46mm pad depth) with a UK rear disc and KAD caliper (49mm pad depth - can someone confirm this please?)
Braking torque: 9.9% improvement
Front/rear bias: 2.3% extra to rear

dandan
06-08-10, 11:44
Rotora

dandan
06-08-10, 11:45
Stoptech

dandan
06-08-10, 11:45
K-Sport

K-Sport 8 Piston caliper - 356mm (54mm pad depth) with a UK rear setup
Braking torque: 0.5% reduction
Front/rear bias: 0.1% extra to rear


K-Sport 8 Piston caliper - 356mm disc (54mm pad depth) with K-Sport 4 Piston rear caliper on 356mm disc
Braking torque: ??% reduction
Front/rear bias: ...(need rear caliper info)


K-Sport 8 Piston caliper - 380mm disc (54mm pad depth) with a UK rear setup
Braking torque: 5.0% improvement
Front/rear bias: 1.5% extra to front


K-Sport 8 Piston caliper - 380mm disc (54mm pad depth) with K-Sport 4 Piston rear caliper on 380mm disc
Braking torque: ??% improvement
Front/rear bias: ...(need rear caliper info)

dandan
06-08-10, 11:45
997 Turbo

Brembo 6 Piston caliper - 350mm (66mm pad depth) with 350mm rear 4 Piston monoblock caliper (60mm pad depth)
Braking torque: 14.6% improvement
Front/rear bias: 9.6% extra to rear


996 Turbo

Brembo 4 Piston caliper - 330mm (60mm pad depth) with 330mm rear 4 Piston caliper (61mm pad depth)
Braking torque: 6.6% reduction
Front/rear bias: 2.6% extra to rear


SL55 AMG

AMG 8 Piston - 360mm (65mm average pad pad depth) with a 330mm rear 4 Piston caliper (45mm pad depth)
Braking torque: 7.7% improvement
Front/rear bias: 0.2% extra to front

Paul Mac - I know the front pads are extremely deep at something like 80mm with the extra material around the mounting lugs. Would you say the 65mm "average" pad depth seems accurate?

Edit: (I just changed the rear pad depth to 45mm - thanks)

dandan
06-08-10, 11:47
Alcon

Alcon 6 Piston Monoblock - 365mm (54mm pad depth) with a UK rear setup
Braking torque: 10.9% improvement
Front/rear bias: 3.1% extra to front


Only seen this kit in one place - Autralia!! http://www.tweakit.net/shop/product_info.php?cPath=57_228_229_243&products_id=1506

dandan
07-08-10, 09:00
Others



Alcon 6 Piston Monoblock - 323mm (54mm pad depth) with a UK rear setup
Braking torque: 0.3% improvement
Front/rear bias: 0.1% extra to front


Alcon 6 Piston Monoblock - 325mm (54mm pad depth) with a UK rear setup
Braking torque: 0.8% improvement
Front/rear bias: 0.3% extra to front


Alcon 6 Piston Monoblock - 330mm (54mm pad depth) with a UK rear setup
Braking torque: 2.1% improvement
Front/rear bias: 0.6% extra to front


Alcon 6 Piston Monoblock - 343mm (54mm pad depth) with a UK rear setup
Braking torque: 5.4% improvement
Front/rear bias: 1.6% extra to front


Alcon 6 Piston Monoblock - 355mm (54mm pad depth) with a UK rear setup
Braking torque: 8.4% improvement
Front/rear bias: 2.4% extra to front

Wez
07-08-10, 09:27
Great info :thumbs:

Could you add the Alcon on a smaller stock sized disc?

Tricky-Ricky
07-08-10, 10:02
Great stuff, interesting and very informative:thumbs:

Edit, also should have added very surprising in some cases.

dandan
07-08-10, 10:08
Cheers chaps - just making a few changes to make it more understandable.

Originally I had the improvements/reductions based on the front calipers and used the bias to tell the rest of the story. The more I thought abut it the more unfair this seemed as, for example, the 997 turbo makes use of immensely powerful rear brakes...somehow.

The percentages for improvements/reductions are now based on both front and rear totals compared to the UK's front and rear totals. That is why some of the data has disappeared where I have no rear caliper info.



A couple of questions to anyone looking...

1. Does anyone have a Rotora or Stoptech kit they could take some measurements off?

2. Could any of the Brembo users tell me the rear caliper piston size please?

3. Could any of the AP users tell me the rear caliper piston size please and ideally the part number of the caliper too?

dandan
07-08-10, 10:25
Great info :thumbs:

Could you add the Alcon on a smaller stock sized disc?

Done - jigged a few things around so post 9 has it in.

Wez
07-08-10, 10:41
Done - jigged a few things around so post 9 has it in.

Top stuff, how about with 325, 330, 343 and 355 disc sizes, I wonder what I could squeeze under my 17" wheels ;)

dandan
07-08-10, 11:27
Top stuff, how about with 325, 330, 343 and 355 disc sizes, I wonder what I could squeeze under my 17" wheels ;)

Done.

Wez
07-08-10, 11:53
Done.

Top stuff :thumbs:

How does pad area come into play in this or are you just comparing the force applied between pad and disc?

The reason I ask is that Alcon have various 4 pot calipers where in fact the pad area is greater than the 6 pots.

4 pot B-type http://www.alcon.co.uk/Catalog/9.pdf
32mm disc
300-330 disc diam
133cm2 pad area
pad thickness 16

4 pot K-type http://www.alcon.co.uk/Catalog/10.pdf
32mm disc
295-355 disc diam
152cm2 pad area
pad thickness 20

6 pot http://www.alcon.co.uk/Catalog/11.pdf
32mm disc
242-380 disc diam
74cm2 pad area
pad thickness 18

dandan
07-08-10, 12:19
The area doesn't play a direct role. The clamping force is generated in the hydraulic system and acts over the piston area(s). This force is applied direct to the back of the pad and then that exact same force is applied to the disc face (no force is "lost" going through the pad).

Pads of different areas can still only transmit the force they get applied to them from the piston(s). None of that force is lost and the pad can't generate any more force on its own - it all comes from the pistons. The contact pressure between the pad and disc will change as pad size changes...more area = less contact pressure but the applied force doing the braking is still the same. There are other effects of contact pressure changes (and pad size and material - not least pad and disc wear) but I wasn't going to get into any of those here as they don't affect the maths for the brake torque (similar to heat and caliper stiffness).

Now if the pad depth (or height depending on how you want to think of it) changes then that does have to be taken into account. The force acting on the disc has to be applied at a certain radius in order to get the brake torque. This radius is usually referred to as the effective radius and that is the disc radius minus half the pad depth.

So a 360mm disc with a 60mm deep pad will have an effective radius of 150mm. The same disc with a 46mm deep pad will have an effective radius of 157mm meaning that the clamping force is applied closer to the edge of the disc. This will increase the braking torque.

A good example to make you think about this is the AP CP5555 vs Brembo Monoblock. The AP's pad depth is pretty big at 54mm compared to the Brembo's 49mm and yet the AP still generates more torque on the same size disc....reason being the AP has more piston area. If you put a 49mm deep pad in the AP caliper it would generate a tiny bit more brake torque than the UK spec whereas the Brembo is approx 4% shy of the UK spec.

So basically ... pad depth plays a direct role. If the disc face design and pad retention mechanism will allow it, the brake torque and bias can be adjusted by altering the pad depths. This isn't ideal as the discs are designed to work with a particular depth pad in order to stabilize the disc temperature variations but it can be done...and people do it.

Wez
07-08-10, 13:22
So is it correct to assume that a larger pad area would be better at dissipating heat therefore more fade resistant but offers less pad to disc contact pressure if the same braking force is applied?

The pad thickness's I listed are much lower than the ones you had, how does this change things?

jagman
07-08-10, 15:21
Somewhat flawed,in a perspective point of view:

it's pascals principle in use, the force gained ( multiplied)is from the difference in piston sizes between the input piston ( brake pedal cylinder if you like, and the output piston size ( caliper piston area) , the work difference being the distance of the pistons moved,and the force being the brake pedal pressure multiplied.
Given the master cylinder is the same in all cases .
Let's say 10 lb pressure is applied and multiplied 1000 times so output force is 10000
now let's use 1/2 the output piston area ,(a lot smaller piston indeed) the result is only 5000 ,lots less eh! , but to get the same force as the much bigger first case , then all we have to do is push the brake pedal twice as hard!
But we only applied 10 lb,not the end of the world to simply apply 20 lbs to get the same brake force , despite only half the caliper piston size!!
Now factor that against the different brake piston areas and make a guess at how much pedal pressure we make!!
Then also factor the difference in pad areas compared to piston areas to get the force / area
it's not that hard to add foot pressure to the brake pedal and lots cheaper

dr_jekyll
07-08-10, 15:35
good stuff , informative and usefull :thumbs:

jagman
07-08-10, 15:43
I googled it .
Typical ratios for master cylinder are around 30 to 1
too much can be as bad as too little.
And of course the ABS will kick in way before you approach any maximum pedal pressure.
Someone could I guess google how much % pedal force it typically kicks in at , but for sure you will have a lot more leg force left than the system could use , and any excess brake force is pointless as the wheels are locked up :d

Tricky-Ricky
07-08-10, 15:59
I think maybe you need to clarify about the pad thickness or depth, as on my first read i took it to mean the actual thickness of the pad, IE pad material between the backing metal and disc, maybe me being too literal, or thick:innocent:

But i do think others who do not have a technical grasp on things may misconstrue the info because of this.

Also there is a big variable, IE force applied to the peddle, how do you quantify that?

dandan
07-08-10, 16:22
Somewhat flawed,in a perspective point of view:

it's pascals principle in use, the force gained ( multiplied)is from the difference in piston sizes between the input piston ( brake pedal cylinder if you like, and the output piston size ( caliper piston area) , the work difference being the distance of the pistons moved,and the force being the brake pedal pressure multiplied.
Given the master cylinder is the same in all cases .
Let's say 10 lb pressure is applied and multiplied 1000 times so output force is 10000
now let's use 1/2 the output piston area ,(a lot smaller piston indeed) the result is only 5000 ,lots less eh! , but to get the same force as the much bigger first case , then all we have to do is push the brake pedal twice as hard!
But we only applied 10 lb,not the end of the world to simply apply 20 lbs to get the same brake force , despite only half the caliper piston size!!
Now factor that against the different brake piston areas and make a guess at how much pedal pressure we make!!
Then also factor the difference in pad areas compared to piston areas to get the force / area
it's not that hard to add foot pressure to the brake pedal and lots cheaper

I like your thinking - stamp harder, save the cash! :)

I'd like to make it clear that I am not a "big brake kit seller" or anything like that - I only posted the numbers up as people have been talking about comparing calipers and kits and how good the UK parts are so I thought I'd share the numbers.


I think maybe you need to clarify about the pad thickness or depth, as on my first read i took it to mean the actual thickness of the pad, IE pad material between the backing metal and disc, maybe me being too literal, or thick:innocent:

But i do think others who do not have a technical grasp on things may misconstrue the info because of this.

Also there is a big variable, IE force applied to the peddle, how do you quantify that?

Good point.... The pad thickness doesn't play any role at all, it is the depth as shown by the blue arrow here. I should have posted that earlier to make it clear.

http://www.mkivsupras.co.uk/imports/2010/08/201.jpg

Hydraulic pressure is directly linked to the braking torque and is completely linear..... double the pressure = double the torque. However it is almost impossible to throw that into the mix to show up anything useful. This comparison was only to compare one brake setup to another for a given set of inputs (same pad compound, same pedal effort, same master cylinder etc).

As Jagman said - stamping on the pedal will increase the hydraulic pressure and increase the braking torque, that is a fact. However, it has to be kept constant in order to make any meaningful comparison between setups or else you could quite rightly say that the brake system off a Fiesta is as good as that on a Supra as long as it's balanced, you can stamp hard enough on the pedal, the seals can handle the pressure and the whole lot can cope with the heat.

Wez
07-08-10, 16:54
I noticed the pad depth when reading a caliper guide earlier, as in its not the pad thickness as I originally thought :innocent:

Some great info in here and I think it would make a great sticky for the tech section once its been trimmed down.

jagman
07-08-10, 17:29
:) I was not intending to belittle your post , but sometimes we get caught up in a world of Data and forget the bleeding obvious ,aided by the tuning world :d
probably the biggest improvement to the braking system would be a small electric fan and some flexible conduit plumbed into the disc dust shield to provide forced cooling
why don't race cars do this ? I don't think they are allowed , we however don't have rules:eyebrows:

JamieP
07-08-10, 17:31
I have some new front and rear pads for my brembos i can measure (tape measure) if you want.

Wez
07-08-10, 18:53
probably the biggest improvement to the braking system would be a small electric fan and some flexible conduit plumbed into the disc dust shield to provide forced cooling
why don't race cars do this ? I don't think they are allowed , we however don't have rules:eyebrows:

Why would you use an electric fan when you can channel the air that you are driving through?

Terminator
07-08-10, 19:31
I thought ducted cooling of brakes was very difficult, very easy to make matters worse. I have certainly found recently that the UK brakes do not like repeated high speed scrubbing. They just fade. Stamping harder just makes matters worse. I think the UK's need top operate at a lower temperature, than some of the bigger brake kits.

Tricky-Ricky
07-08-10, 20:56
I like your thinking - stamp harder, save the cash! :)

I'd like to make it clear that I am not a "big brake kit seller" or anything like that - I only posted the numbers up as people have been talking about comparing calipers and kits and how good the UK parts are so I thought I'd share the numbers.



Good point.... The pad thickness doesn't play any role at all, it is the depth as shown by the blue arrow here. I should have posted that earlier to make it clear.

http://i828.photobucket.com/albums/zz202/danc8000/0c5d71c9.jpg

Hydraulic pressure is directly linked to the braking torque and is completely linear..... double the pressure = double the torque. However it is almost impossible to throw that into the mix to show up anything useful. This comparison was only to compare one brake setup to another for a given set of inputs (same pad compound, same pedal effort, same master cylinder etc).

As Jagman said - stamping on the pedal will increase the hydraulic pressure and increase the braking torque, that is a fact. However, it has to be kept constant in order to make any meaningful comparison between setups or else you could quite rightly say that the brake system off a Fiesta is as good as that on a Supra as long as it's balanced, you can stamp hard enough on the pedal, the seals can handle the pressure and the whole lot can cope with the heat.

Just to add, i wasn't knocking your very informative write up either, just wanted to get certain points clarified for the people who wont necessarily grasp the finer points straight off, and there are those who will pick, so better to have it all covered;)

I agree it should be made a sticky as there is about as much info as anyone contemplating a different/bigger brake set up is ever likely to need, thanks for going to the trouble and all the calc:salute::)

Wez
07-08-10, 21:50
I thought ducted cooling of brakes was very difficult, very easy to make matters worse. I have certainly found recently that the UK brakes do not like repeated high speed scrubbing. They just fade. Stamping harder just makes matters worse. I think the UK's need top operate at a lower temperature, than some of the bigger brake kits.

This is where the difference between road or race compound is highlighted, a race pad can function at much higher temps. On my track car with UK setup, race pads and decent rotors I melted the dust caps and decals on the calipers without experiencing fade ;)

jagman
07-08-10, 22:21
Why would you use an electric fan when you can channel the air that you are driving through?

Great if you are moving , the heat energy is exactly the same whichever brakes you have ,just spread over slightly different surface areas - all the discs centrifuge the heat out and the ducts move heat away from the area while moving along with the wheels .
once stopped in pits or traffic lights there aint a lot of heat being moved , so fans would help ..
"I thought ducted cooling of brakes was very difficult, very easy to make matters worse"
how and why ?

dandan
07-08-10, 22:42
No sweat chaps - don't worry about the questions or "picking" - doesn't bother me :) Like I said, I put this little lot together a while back for myself when trying to make some decisions about a kit.

There's a few bits of info I need to complete what I have so far (Brembo, K-SPort and AP rear piston sizes and confirmation of KAD rear caliper pad depth) and then it'll be reasonably complete and useful.

I have nothing useful on the Stoptech and Rotora so the people running those kits need to come forward :D

Jagman's question about ducting....a lot of people duct to the outer face(s) of the discs rather than feeding the "eye" on the back to pump out through the vanes. This doesn't give ideal temp variations in the discs and can (apparently) lead to problems. Not something I've looked into first hand though.

Jamie - the pad sizes would be useful to check which one of the two in Brembo's catalogue is correct. The length of the blue arrow on the pad picture on the previous page is the key one (the depth or height of the friction material - not the backing plate).

Kirk
07-08-10, 22:48
On my track car with UK setup, race pads and decent rotors I melted the dust caps and decals on the calipers without experiencing fade ;)

To be fair though wez your UK setup isnt quite like everyone elses :p

Realy interesting thread this one, shame i dont understand everything although its probly quite simple :D

jagman
08-08-10, 01:05
Realy interesting thread this one, shame i dont understand everything although its probly quite simple

It is very simple....
Its about energy , the car is moving and has energy built up this energy is transfered during braking
1/2 MVsq = the calculation of energy
1/2 times the mass times the velocity (speed)
the car weighs say 1500 kilo multiplied by its speed (squared)
so a supra going 10 miles an hour and one at 20 miles an hour does not take twice the energy to stop but
1500 x 10x10 = 150000/2
1500 x 20 x20 = 600000 /2
4 times the energy !!!!
so a supra going 170 miles an hour = a shit load of energy:D

All this energy is converted to heat via friction , between the pads and discs , thats a shit load of heat , can you see that no matter how big the discs and pads are its still huge amounts of heat , even with discs twice the size of stock its enough energy to get them glowing hot with a couple of high speed stops
The pads at the front have a sharp edge , this gets hotter and wears more quickly ,so the multi piston calipers can have smaller pistons here to compensate a bit for that .
All this heat has to go somewhere , it goes into the fluid,lines,caliper,pads ,discs,tyres and surrounding air
As the various parts get hot they in turn pass their heat on , a bigger area /size dissipates heat better - but is an extra 1 inch diameter disc going to dissipate that much more heat ?
to aid heat transfer the wheels can direct cooler air over the brakes/hubs/etc , so can cooling ducts in the plastic wheel arch, so can the discs themselves by the small channels between the discs that "throw" out air centrifugally between the discs.
once the car stops so does the cooling !!!! But the metal parts can retain loads of heat for a long time - thats why I suggest cooling fans
Its also why you take your foot off the brake after a big stop , as the pads contact only a small area of the disc and this can exchange heat to them with contact and so warp the discs with different temps across the disc

jagman
08-08-10, 06:24
http://home.wanadoo.nl/this-is-me-at/brembo/brembo.html

Here is a good read , especially the bit about floating discs and the advantages over solids also gives data on energy per cm so rough estimates could be made, given disc sizes larger than stock

jagman
08-08-10, 14:01
From the link above I think it is clear that heat is the main concern, controlling the heat and keeping within limits is the single most improvement in braking
80% of the heat is in the discs themselves.
Most heat is generated at high speed
brake pad pressure not as important as you would think
enclosed wheels don't help
floating discs more heat tolerant
pad compounds dictate heat range
etc etc..


I maintain that electric fan cooling can only help when high speeds are used in braking .

If you never go over 70 you have no worries :innocent:

TLicense
08-08-10, 14:52
We tinkered a bit with fan cooling of brake discs on the Williams back in 2003 I think it was.
The problem was getting the fan to not hinder the normal mass flow at high speeds.
We ended up with a fan being geared off of the wheel axle so it span at incredibly high speed.
Eventually we developed a brake duct that could cool the disc more efficiently anyway.

But yes I totally agree that heat management is probably as big a factor as the mechanical braking torque, which should be born in mind when selecting an upgrade.

jagman
08-08-10, 15:47
In a way the Supra has a bigger challenge than F1 , twice the weight + ,and similar top braking speeds , without the budget or ceramics.
Some recent electric motors , now run astonishing Rpms compared with 2003 .
Small and cheap efficient, fans for low speed and stationary cars would work I feel ,easy to do as well .
I will try it , nothing ventured nothing gained !

paul mac
10-08-10, 21:55
Interesting post Dan, i have a few points though, I presume the figures you are quoting is brake torque. From my hazy recollections of HNC physics i can just about remember that the pad area is in the equation somewhere. You obviously have the pad height but are you presuming the pads are all the same length, what is the formula you are using to calculate your figures, are you using a standard coefficient of friction as this will increase (or decrease) dependent on the area of the friction material.



ps my rear pad height is 45mm :d

dandan
10-08-10, 23:04
Pad size is 100% not in there Paul. It plays no part although a lot of people think it does. The area cannot affect the coeff of friction, the coefficient of friction is a physical property of materials in contact and is not related to size.

This comparison is done with an arbitrary pressure applied to the piston areas to generate the clamping force. This clamping force is applied at the effective radius and the coefficient of friction is used to give the retarding force (acting at the effective radius) which is obviously 90degrees to the clamping direction.

There is a calculator here that looks like it follows the same approach...I'd need to run some comparison numbers at work to see if they tie exactly.

http://www.tceperformanceproducts.com/brake_bias_calculator.html

And a couple of halfway interesting links where they mention pad area...

http://www.automotivearticles.com/Braking_Basics_and_Break_in_Practice.shtml
http://www.driverstechnology.co.uk/brake-pad-area.htm

paul mac
10-08-10, 23:27
yes i think your right now you explain it (damm that red wine) i may be confusing friction force here, as i said its all a bit hazy :d, i am sure i remember contact area coming into the equation though i'll have to get out the old books, so the percentage figure you quote is clamping force generated by the hydraulics and not brake torque

dandan
11-08-10, 07:14
It is brake torque but that is only related to clamping force by the coefficient of friction. For comparison's sake it can be thought of as the same thing if the coefficient of friction is constant. For my numbers I was using a shade under 0.4 but it doesn't really matter as I am not looking for absolute values - only relative values between different setups.

What I was really doing was investigating brake bias on big brake kits to see how far they deviate from OEM and comparing that to my options for my own custom made kit. To get the brake bias you need the front and rear braking torque but once again - only in relative terms.

garethr
11-08-10, 07:47
IIRC the variables in the calculation are:
hydraulic pressure
coefficient of friction
effective radius (disc diameter - actually slightly outboard of the pad centre)
caliper piston area (of one side of the caliper).

For the same driver, the same master cylinder, the same pad compound, and the same disc material, you can ignore the first two, so for comparison purposes you need the total piston area for one side of the caliper and the effective radius.

jagman
11-08-10, 09:50
Perhaps a little more perspective is needed ;
Even the crappiest pads/discs have the ability to lock up the wheels / reach abs limits (we are not talking about for how long or many times)
The Ratio for brake pressures is fixed -ie the master cylinder
The maximum retardation is locked wheel and abs , but the rate of retardation is controlled and going to be mostly due tyre selection ,compounds etc
If say larger front discs/pads were fitted the maximum retardation remains the same , however the rate that this happens may be faster , this faster rate of application would move weight faster to the front of the car (and more of it)
This would increase the loading /heat to the front brakes , and reduce the rear loading ( possibly lock up the rears too early?)
My initial feelings are tyres are the major factor in braking ability,more than the discs /calipers/pads
Discs/caliper/pads will determine "feel" ie reaction times and pedal feel , and how much load you move forewards onto them ie the point at which the rear locks up - and to work this out will give you the problem that it is tyre dependent and road surface dependent
My 2 pence worth

dandan
11-08-10, 10:09
Jagman - I think it's fair to say that your "perspective" is something that has already been talked about a lot here on the board and nobody disagrees with it or is trying to say anything to the contrary. This is about direct comparisons between different setups....

Ultimately tyres, weight transfer heat etc are key limitations - nobody is disputing that and I'm not trying to show anything different by looking at the numbers. I'm not sure if you're getting the wrong end of the stick and trying to put forward an argument of some sort but nobody is actually arguing :)

Wez
11-08-10, 10:14
Agreed, the numbers are just to show direct comparisons between different setups with most variables at a constant between setups, we all know there are lots of other factors involved but this is a like for like comparison.

Thanks again Dan :thumbs:

jagman
11-08-10, 10:55
So what is the comparrisson? simply some mathmatical size difference that becomes meaning less , some "force" difference that also becomes meaningless
Toyota would have done all the calcs and based on their tyres ,caliper ,pads ,abs , wheels sizes, road surfaces etc
So any changes to improve , by going bigger can only be assessed by feel , weight saved , durability,heat recovery,pad wear ,dust and even then given perfect tyre tread and pressures and compounds and becomes anecdotal rather than calculated

dandan
11-08-10, 12:04
So what is the comparrisson? simply some mathmatical size difference that becomes meaning less , some "force" difference that also becomes meaningless
Toyota would have done all the calcs and based on their tyres ,caliper ,pads ,abs , wheels sizes, road surfaces etc
So any changes to improve , by going bigger can only be assessed by feel , weight saved , durability,heat recovery,pad wear ,dust and even then given perfect tyre tread and pressures and compounds and becomes anecdotal rather than calculated

To be honest I'm not exactly sure what your answer to your own questions is trying to say or whether you are actually asking something you want an answer to. Anyway, I'll try to answer your question as best I can.

The comparison is a mathematical one...yes 100%.

For a given coefficient of friction, pedal force, pedal ratio, and boost ratio it tells you how the braking torque and more importantly the braking bias changes for various aftermarket options available. That's it.

If for example you decided to upgrade to KAD's six pot front caliper on your OEM 323mm disc then it's not obvious or published anywhere that the available braking torque on your front axle drops by almost 8%. That drop also ties in with a shift in the brake bias of almost 3% to the rear. A lot of people have absolutely no comprehension or appreciation of this and believe whatever they read thinking that they have "upgraded" their brakes. This is not necessarily the case and this is what I was looking into when I did the comparison. There is no error in the maths and the comparison is valid as long as you know what the assumptons and limitations are.

On a slightly different track, Paul Mac adapted an AMG kit to fit.....excellent, made a smashing job of it. :thumbs: However, if someone for example adapted the 997 turbo kit to fit they would be throwing the brake bias to the rear by almost 10% without means to address this. This is exactly the sort of thing I wanted to find out for my own benefit...and I did.

I'm not arguing against anything Toyota have done, quite the contrary. I am looking to see how the big brake kits we could lay our hands on have actually deviated from the original bias.

Does that answer your question?

jagman
11-08-10, 16:41
The braking torque is the twisting action caused by the drum or disc on the shoes or caliper anchors during the application of brakes. The amount of torque is determined by the effective axle height and stopping force between the tyre and road surface.
Brake torque on the front wheels is absorbed by the knuckle and suspension control arm. In rear, it is absorbed by the axle housing and the leaf spring or control arm. Braking torque during an emergency stop is much higher than accelerating torque at full throttle. Brake supporting and anchoring members must, therefore, have sufficient strength to withstand these high braking loads.

http://www.the-crankshaft.info/2009/09/braking-system.html

If you have a read and see what you are trying to establish is possible given the variables and fixed data -and the only data you have ie the size of the discs and area of pads to use for comparrisons
Look at the brake bias bit in particular

dandan
11-08-10, 17:23
The braking torque is the twisting action caused by the drum or disc on the shoes or caliper anchors during the application of brakes. The amount of torque is determined by the effective axle height and stopping force between the tyre and road surface.
Brake torque on the front wheels is absorbed by the knuckle and suspension control arm. In rear, it is absorbed by the axle housing and the leaf spring or control arm. Braking torque during an emergency stop is much higher than accelerating torque at full throttle. Brake supporting and anchoring members must, therefore, have sufficient strength to withstand these high braking loads.

http://www.the-crankshaft.info/2009/09/braking-system.html

If you have a read and see what you are trying to establish is possible given the variables and fixed data -and the only data you have ie the size of the discs and area of pads to use for comparrisons
Look at the brake bias bit in particular

I read it - what is it about the brake balance that you makes you say "Look at the brake bias bit in particular"? Once again I think I am missing the point of your post, sorry.

paul mac
11-08-10, 18:27
It is brake torque but that is only related to clamping force by the coefficient of friction. For comparison's sake it can be thought of as the same thing if the coefficient of friction is constant. For my numbers I was using a shade under 0.4 but it doesn't really matter as I am not looking for absolute values - only relative values between different setups.

What I was really doing was investigating brake bias on big brake kits to see how far they deviate from OEM and comparing that to my options for my own custom made kit. To get the brake bias you need the front and rear braking torque but once again - only in relative terms.

i'm with it now Dan and i can only commend you on your approach here to quantify this topic, i have long suspected what you have found and posted my suspicions here http://www.mkivsupra.net/vbb/showthread.php?t=137208&highlight=big+brakes, hard figures are beyond argument, i also kind of killed this thread :innocent:http://www.mkivsupra.net/vbb/showthread.php?t=168382&highlight=big+brakes at post #41

jevansio
12-08-10, 08:33
I've just read this link:

http://www.carbibles.com/brake_bible.html

Does anyone not feel it a little unfair that we are "rating" these different brake setups against each other based on the force the piston can apply when in reality there is a lot more at work.

dandan
12-08-10, 08:49
I wasn't rating them Jay - I was trying to decide which to buy.

To truly rate them you'd really have to go to town with caliper stiffness, noise, dust, weight, inertia, heat transfer (good or bad), wheel size limitations etc etc. I don't have the time or money to buy all those kits and do the testing. If anyone wanted to help then I'd be happy to organize some tests to quantify some of the stuff but to be honest I don't think anyone would be interested.

Something to bear in mind that has a massive effect is the pads....but in reality pad selection makes no difference here as you can pretty much use any pad in any kit so it's irrelevant.

Edit: To kind of answer your question..... I think it is more than fair to compare these kits based on available braking torque (or piston area and effective radius). With an appreciation of caliper stiffness (and a detailed knowledge of the two piece floating/fixed design of every kit here) I had more than enough info to decide what to do or which to buy. Without the braking torque and bias figures I could not have made any sort of informed choice.

jevansio
12-08-10, 09:00
Trouble is if you are using these numbers to "decide" what to buy, is that in itself not flawed when you have discounted so much of what constitues a brake kit that performs to your needs?

EDIt sorry I see you mean as additional info, not soley on these nubers :D

jevansio
12-08-10, 09:03
PS I think we do need a day out test where we measure actual stopping distances of various setups at different speeds on different tyres :D

dandan
12-08-10, 09:05
i'm with it now Dan and i can only commend you on your approach here to quantify this topic, i have long suspected what you have found and posted my suspicions here http://www.mkivsupra.net/vbb/showthread.php?t=137208&highlight=big+brakes, hard figures are beyond argument, i also kind of killed this thread :innocent:http://www.mkivsupra.net/vbb/showthread.php?t=168382&highlight=big+brakes at post #41

Brakes are very subjective. Like suspension setups, people want different things and within the limts of road tyres and road usage temperatures it is very difficult to generate a real life comparison that anyone could understand or buy into as everyone places importance on different things.

Some like massive initial bite as it fills them with confidence, some like to save money, some like constant braking throughout a stop, some like that braking force to increase through the stop. Some can live with noise, some hate removing monoblock calipers to change pads Some people just want to fill their wheels and have nice colours in there. Some like a particular brand so it's hard to come up with anything meaningful.

I wanted to know where to best spend my money for improved performance. In my mind that "performance" is a combination of balance, weight, caliper stiffness and pedal feel, noise, serviceability and reliability.

dandan
12-08-10, 09:13
Trouble is if you are using these numbers to "decide" what to buy, is that in itself not flawed when you have discounted so much of what constitues a brake kit that performs to your needs?

EDIt sorry I see you mean as additional info, not soley on these nubers :D

What I didn't want to do is post up a list of my perceived advantages and disadvantages to everyone's brakes.....far too contentious and probably wouldn't sit too well with the vendors :D

If I were to be buying a kit I would consider weight, stiffness, disc internal cooling design, piston material, caliper material, piston area, effective radius, seal design, disc and pad availability, reputation of parts on same cars (not in F1, Indy etc etc), floating design, noise and wheel limitations. I could post up lots of information and facts on what Brembo, KAD, AP, Alcon and a few OEM systems have to offer in those areas but I don't really want to as people will get a bit defensive about what they have and which factor is most important to them. :)

jagman
12-08-10, 09:18
Hence my perspective comment , in relation to all variables the size of the caliper almost becomes meaningless, differences with calculated bias of 1-2 % compared with 15% friction pad weight shift changes .
Ultimately the best kit has the best heat removal ability and thats a job to compare ,and pad selection is a biggie .
expensive BBK and cheap tyres also a bit daft!

jevansio
12-08-10, 09:33
What I didn't want to do is post up a list of my perceived advantages and disadvantages to everyone's brakes.....far too contentious and probably wouldn't sit too well with the vendors :D

If I were to be buying a kit I would consider weight, stiffness, disc internal cooling design, piston material, caliper material, piston area, effective radius, seal design, disc and pad availability, reputation of parts on same cars (not in F1, Indy etc etc), floating design, noise and wheel limitations. I could post up lots of information and facts on what Brembo, KAD, AP, Alcon and a few OEM systems have to offer in those areas but I don't really want to as people will get a bit defensive about what they have and which factor is most important to them. :)
Oh I know bud :)

The only reason I brought anything up is that UK spec brakes have this "reputation" of being unbeatable, and unsuspecting readers will take this "braking force" as being the deciding factor of how good a brake system is.

I guarantee in a future argument on how good UK brakes are over BBKs the data in this thread will be brought up :D

Terminator
12-08-10, 09:47
As long as anyone reading this thread is aware of the numerous factors that influence brake performance, there should not be a problem. The increase or decrease in braking torque and shift or otherwise of brake bias, is very useful information, which up to now has not been available, and is infinitely better than the seat of the pants "these brakes are amazing" recommendation.

The full UK setup is an excellent braking system, this thread least gives a comparison of brake torque and bias against a benchmark standard that we have not had before. I hope this thread gets tidied up and put in Tech FAQ with the appropriate health warnings and perhaps links to some of the excellent technical information that has been added. If the information collated stops one person making a drastic and possibly dangerous choice of brakes, it will have been more than worth while. When members start asking questions about possible brake buys, we have some where to point them for objective rather than subjective information.

This thread, when combined with other research I carried out, has certainly reassured me that my choice of callipers and discs has not altered brake bias.

Ian C
12-08-10, 10:29
I'm keeping an eye on this to poach for a tech article, don't worry :)

dandan
12-08-10, 11:09
I have the data in more sensible formats (see example below) which I can post up as well but I was waiting for at least the "AP Race" and "Brembo C" rear caliper info to surface before I do that. I also want to double check the numbers as it was some time ago that I put the bulk of this together :D

If "we" wanted to make a useful BBK type thread (rather than opinion based feelings about how good certain setups are) I could post up some facts about piston materials, float mechanisms, bridge design etc to give people an appreciation of how various kits differ. No opinion or recommendations....just the technical differences so people could weigh up which feature/design element/colour is important to them. That could take some time though!

TLicense
12-08-10, 11:11
Do it Dan, do it. ;)

Wez
12-08-10, 11:12
More graphs, everyone loves a good graph :thumbs:

Terminator
12-08-10, 13:38
More graphs, everyone loves a good graph :thumbs:

Oh yes now you're talking:p

Ian C
12-08-10, 15:15
Graphs :love:

dandan
16-08-10, 13:32
Do it Dan, do it. ;)


More graphs, everyone loves a good graph :thumbs:


Oh yes now you're talking:p


Graphs :love:

You guys crack me up - gotta love a good visual aid! :D

I'll be off work for a few days near then end of the month so I'll try to put something together then about the various float configurations and materials. I have enough info and pics to explain the floating mechanism on the Brembo GT kits, Alcons road and race kits, various AP setups and a couple of others. If somebody wants to purge it or amend it for some sort of FAQ type thread then that's fine by me.

In the meantime if anyone can help with the following it would be great as I could get a more complete list uptogether.

1. Brembo BBK rear caliper piston diameters

2. Brembo BBK rear caliper pad depths

3. AP race rear caliper piston sizes and pad depth (as per Whifbitz AP BBK)

4. K-Sport - any of the rear caliper piston diameter and pad depths

5. Stoptech - do any of you chaps with Stoptech kits fancy chipping in?

GlennK
20-08-10, 09:34
One other useful thing to add to the comparison table please:

Weight deltas (+,-) wrt UK F,R brake kits

Thanks

Wez
20-08-10, 10:17
One other useful thing to add to the comparison table please:

Weight deltas (+,-) wrt UK F,R brake kits

Thanks

:yeahthat: very useful indeed.

dandan
20-08-10, 16:12
Good idea - this will need members to post up info though.

I have all the weight info for OEM and Alcon 4 pot and 6 pot monoblocks...nothing else though.

dandan
27-08-10, 20:09
All these setups (Brembo, AP, Stoptech, Alcon etc) have subtle differences and it's not easy to tabulate it all but I think once I have jotted some of it down it'll be easier to pick out the obvious stuff to compare in a few tables along with some supporting text and images.

....Data below is for example purposes only.....

Brembo GT Monoblock


Complete kit weight for front axle: 28kg
Complete kit weight for rear axle: 25kg


http://www.mkivsupras.co.uk/imports/2010/08/1183.jpg

Disc Size

Front 356mm
Rear 345mm


Brake Torque and Bias

http://www.mkivsupras.co.uk/imports/2010/08/1184.jpg

Calipers and Materials

Cast aluminium monoblock front caliper
Six chrome plated steel pistons - 36, 30, 28mm diameter
Front bare caliper weight (no pads or mounting brackets) ??kg
Front caliper weight including pads and mounting brackets ??kg
Steel mounting bracket


Cast aluminium two piece bolted rear caliper
Four chrome plated steel pistons - 32, 30mm diameter
Rear bare caliper weight (no pads or mounting brackets) ??kg
Rear caliper weight including pads and mounting brackets ??kg
Steel mounting bracket


Float Mechanism

Float in disc
Oval hole in disc (typically an 8.15mm by 10.25mm)

http://www.mkivsupras.co.uk/imports/2010/08/1185.jpg


Round hole in bell
Bobbin passes through disc and bell transmitting torque from one to the other
Bobbin pushes through from front of bell and has female thread (like a nut)

http://www.mkivsupras.co.uk/imports/2010/08/1186.jpg


Bolt comes through from rear of disc and screws into bobbin
Bobbin is longer than the combined thickness of the disc and bell so bolt “does up” against the bobbin and the disc and bell are left to rattle freely sliding back and fro on the bobbin


http://www.mkivsupras.co.uk/imports/2010/08/1187.jpg

http://www.mkivsupras.co.uk/imports/2010/08/1188.jpg


McLaren anti rattle shim (usually on back of disc) included on alternate fixings (regular washer used elsewhere)




So.....would this info be useful/welcome?
Anything else people want to know?

Wez
27-08-10, 20:28
I would say so yeah, great write up matey :thumbs:

Kirk
27-08-10, 20:51
Definatly a most useful thread for people who research before buying :)

dandan
28-08-10, 10:33
OK cool - I'll knock something up with this sort of info.

If we can convince any members/traders to take a few measurements we can end up with a very complete comparison somewhere down the line...

dandan
30-08-10, 11:34
How do I create a table guys? Should I just paste one in as an image - would that be easiest?

So far I have the following common "Kits" completed:

Brembo 14" monoblock with 13.58" rear
AP 356mm road kit with AP/Stillen 330mm rear
AP 356mm road kit with UK rear
KAD 17" front kit with UK rear
KAD 18" 356mm kit (six pot rear caliper)
KAD 19" 378mm kit (six pot rear caliper)

I am waiting for some rear caliper info from Paul Whiffin to allow me to finish these two and add them straight in:

Garage Whifbitz 362mm front and 343mm rear race kit
Garage Whifbitz 343mm rear road kit (to compliment AP's 356mm front road kit)


I am also waiting for some feedback from jme on his KSport 356mm front and rear kit and then I can add that.

And I could also include two specials as I have the info for these although they aren't real kits:

AMG Brembo 8pot 360mm front and 4 pot rear 330mm kit (Paul Mac's)
Alcon 6 pot 365mm front monoblock and Alcon 4 pot rear 324mm monoblock (Mine)


Does anyone have a Stoptech kit and want to help out by supplying some info?



No.|Manufacturer|Rating|Size|etc
1|Brembo|5|etc |etc
2|Alcon|5|etc |etc


.

Steve
30-08-10, 11:40
Added a table to your post Dan, you should be able to copy/paste/edit as needed.

Luxluc
30-08-10, 17:40
How do I create a table guys? Should I just paste one in as an image - would that be easiest?

So far I have the following common "Kits" completed:

Brembo 14" monoblock with 13.58" rear
AP 356mm road kit with AP/Stillen 330mm rear
AP 356mm road kit with UK rear
KAD 17" front kit with UK rear
KAD 18" 356mm kit (six pot rear caliper)
KAD 19" 378mm kit (six pot rear caliper)

I am waiting for some rear caliper info from Paul Whiffin to allow me to finish these two and add them straight in:

Garage Whifbitz 362mm front and 343mm rear race kit
Garage Whifbitz 343mm rear road kit (to compliment AP's 356mm front road kit)


I am also waiting for some feedback from jme on his KSport 356mm front and rear kit and then I can add that.

And I could also include two specials as I have the info for these although they aren't real kits:

AMG Brembo 8pot 360mm front and 4 pot rear 330mm kit (Paul Mac's)
Alcon 6 pot 365mm front monoblock and Alcon 4 pot rear 324mm monoblock (Mine)


Does anyone have a Stoptech kit and want to help out by supplying some info?



No.|Manufacturer|Rating|Size|etc
1|Brembo|5|etc |etc
2|Alcon|5|etc |etc


.

I will pm you in a couple of days Dan to get the info you want.
I've been busy with work lately, but I see some quiter days coming soon. I have the STOPTECH ST40 kit (4 pot / disc size 355 x 32mm) front and rear.

Cheers

Luc

dandan
31-08-10, 08:32
Added a table to your post Dan, you should be able to copy/paste/edit as needed.

Thank you Steve, I'll give it a go....looks like it might be a bit long winded though as my table is pretty big :)


I will pm you in a couple of days Dan to get the info you want.
I've been busy with work lately, but I see some quiter days coming soon. I have the STOPTECH ST40 kit (4 pot / disc size 355 x 32mm) front and rear.

Cheers

Luc

That would be great Luc - I'm sure everyone would love to know how the Stoptech kit compares.Give me a shout when you're free to do a few measurements....the most awkward one is measuring the piston sizes (anywhere from 28-42mm in 2mm steps) but according to this info it can be done without taking the caliper off :)

http://www.zeckhausen.com/How_to_Measure_Pistons.htm

Luxluc
31-08-10, 18:49
No prob Dan.

I am busy with my Supe getting i through MOT over ther right now (it failed). It passed the last 2 years without problems, but suddenly they want German TUV papers for the single conversion, coilovers, Stoptech brakes, etc.

I got the necessary papers today, but they are still not happy as the TUV guy forgot to put my 19" rims on the certificate .. so I am heading back to germany again onThursday.

By the end of the week, everything should be fine .. so I will pm you on Friday.

Cheers

P.S. I will take the wheels off during the W-E to lower the coilovers (I had to raise them to access the MOT station) .. so I can also take some pics if needed.

dandan
05-09-10, 21:13
No prob Dan.

I am busy with my Supe getting i through MOT over ther right now (it failed). It passed the last 2 years without problems, but suddenly they want German TUV papers for the single conversion, coilovers, Stoptech brakes, etc.

I got the necessary papers today, but they are still not happy as the TUV guy forgot to put my 19" rims on the certificate .. so I am heading back to germany again onThursday.

By the end of the week, everything should be fine .. so I will pm you on Friday.

Cheers

P.S. I will take the wheels off during the W-E to lower the coilovers (I had to raise them to access the MOT station) .. so I can also take some pics if needed.

Good man - thanks. That sounds like a total ball ache with the MOT, hope you get it all sorted.

dandan
06-09-10, 11:29
OK well let's try these.

All previous caveats apply regarding variables kept the same such as force applied to pedal, pad friction material, temperature etc. No allowance is made for caliper stiffness, wear rates of floating mechanisms, noise from floating mechanisms, corrosion, serviceability, availability of replacement parts etc.

These things do play a role but in order to make any fair comparison (and especially to calculate the front to rear brake bias) they have to be ignored. As far as I am aware nobody markets a kit that has to use a different pad compound front to rear in order to get the correct bias and the figures certainly seem to support this.

I didn't really want to comment on anything other than the mechanicals of these kits as anything else (perhaps with the exception of caliper stiffness and its importance for brake feel) could be seen as opinionated and not fair on traders etc. This is a non opinion based comparison of the mechanical design of these kits. Please let me know if you think I have made any mistakes and I will be more than happy to change them.

Thank you to the people that helped with weights, measurements etc - Jevansio, Lee P, Luxluc, M5W TT, Ricky49, Paul Mac and probably a few more. :thumbs:

I am waiting on some info from Mr Whiffin for the "Garage Whifbitz AP Race" kit and also the "Garage Whifbitz Road" AP rear kit. As with the Stoptech info from Luxluc - once I have it, I will add it to these comparisons.

Hopefully someone somewhere will find this interesting or useful! :)


Basic comparison:

http://www.mkivsupras.co.uk/imports/2010/09/387.jpg


Bias in graphical format:

http://www.mkivsupras.co.uk/imports/2010/09/388.jpg


Available brake torque in graphical format:

http://www.mkivsupras.co.uk/imports/2010/09/389.jpg

dandan
06-09-10, 11:30
And here are a few posts which help show what the floating hardware looks like for some of these kits. With any luck people can look at the pictures and the table and see where the "float" actually happens, which bits are likely to wear etc etc.


Brembo Monoblock

http://www.mkivsupras.co.uk/imports/2010/09/390.jpg

Brembo Floating Hardware - Front and Rear

http://www.mkivsupras.co.uk/imports/2010/09/391.jpg

http://www.mkivsupras.co.uk/imports/2010/09/392.jpg

http://www.mkivsupras.co.uk/imports/2010/09/393.jpg


KAD 378mm Kit

http://www.mkivsupras.co.uk/imports/2010/09/394.jpg

KAD (AP) Floating Hardware - Front Only
http://www.mkivsupras.co.uk/imports/2010/09/395.jpg

http://www.mkivsupras.co.uk/imports/2010/09/396.jpg

http://www.mkivsupras.co.uk/imports/2010/09/397.jpg

dandan
06-09-10, 11:30
AP Road Kit

http://www.mkivsupras.co.uk/imports/2010/09/398.jpg

AP Non Floating Bolted Hardware - Front and Rear

http://www.mkivsupras.co.uk/imports/2010/09/399.jpg

http://www.mkivsupras.co.uk/imports/2010/09/400.jpg

http://www.mkivsupras.co.uk/imports/2010/09/401.jpg


Stoptech ST40

http://www.mkivsupras.co.uk/imports/2010/09/402.jpg

Stoptech Floating Hardware - Front Only (Rear float/bolt hardware TBC)

http://www.mkivsupras.co.uk/imports/2010/09/403.jpg

http://www.mkivsupras.co.uk/imports/2010/09/404.jpg

dandan
06-09-10, 11:31
Alcon Monoblock - Custom for front and rear (but a front kit is available)

http://www.mkivsupras.co.uk/imports/2010/09/405.jpg

Alcon Floating Hardware - Front Only

http://www.mkivsupras.co.uk/imports/2010/09/406.jpg

http://www.mkivsupras.co.uk/imports/2010/09/407.jpg


AMG Brembo - Custom for front and rear

http://www.mkivsupras.co.uk/imports/2010/09/408.jpg

AMG Floating Hardware - Front and Rear

http://www.mkivsupras.co.uk/imports/2010/09/409.jpg

http://www.mkivsupras.co.uk/imports/2010/09/410.jpg

http://www.mkivsupras.co.uk/imports/2010/09/411.jpg




AP Race Garage Whifbitz (Pics and info for table coming soon hopefully)

TLicense
06-09-10, 12:51
Awesome stuff Dan! :thumbs:

The info on the AP / Stillen rear kit just needs a slight correction though, as I'm pretty sure the mounting bracket is aluminium, and I'm certain the disc bell is. (I had to drill a hole into it to access the handbrake adjustment mechanism).

dandan
06-09-10, 12:56
Awesome stuff Dan! :thumbs:

The info on the AP / Stillen rear kit just needs a slight correction though, as I'm pretty sure the mounting bracket is aluminium, and I'm certain the disc bell is. (I had to drill a hole into it to access the handbrake adjustment mechanism).

No sweat mate - be good if you could check your Stillen kit for us. The pdf they sent me says the bell is iron and the bracket is 1018...."for maximum strength" :D

Edit: Could yours be an early kit perhaps? This is an AP0550 kit.

Kirk
06-09-10, 20:12
Fantastic work dan :thumbs:

The only thing is the basic comparison table can be a little harsh on your eyes :D

Alcon look to be a nice upgrade :cool:

dandan
06-09-10, 20:37
I tried a few colours for the table to try to get it clear and crisp but it wasn't easy. As it's so bloody big it loses clarity when it's shrunk and converted to a pic. I'll try some other colours and see what the general opinion is.

The Alcons are truly excellent calipers and the float hardware is robust and silent but unforunately there's only a front kit available off the shelf. Anything for the rear would have to be custom made. :(

Kirk
06-09-10, 20:43
The colour scheme is fine just the words are a little small for some eyes :D

Your doing a alcon rear setup with UK disc correct?

dandan
06-09-10, 20:55
The colour scheme is fine just the words are a little small for some eyes :D


Yep sorry about that! Perhaps I should split it into two tables and make everything bigger, especially as a couple of people have got in touch about adding details for other kits. I could also remove the two custom kits (the full Alcon setup and Paul's AMG Brembo setup) as they're not easily available to everyone - that would knock out two columns.



Your doing a alcon rear setup with UK disc correct?

That's the plan but it's on hold at the moment as I've got one arm in a sling - typical! I have everything I need except the rear pads (hopefully arriving this week) and rear caliper brackets.

JustGav
06-09-10, 20:57
Absolutely fantastic...

Might suggest taking the table out and moving it a new thread for reference and loose the chit-chat.

Kirk
06-09-10, 21:02
That's the plan but it's on hold at the moment as I've got one arm in a sling - typical! I have everything I need except the rear pads (hopefully arriving this week) and rear caliper brackets.

Ill keep my eyes pealed. Ive always been a fan of alcons :cool:

patrik
06-09-10, 22:33
Great Job!

I would some info added if possible?

The j spec brakes and the Uk brakes in the big table thingy

because then newbies or people like me dont have to search the forum for dimension and weights and such.

since you have done such an awesome job so far maybe you can put it in pretty pls :-)

i almost had a setup of porsche gt2 brakes but after looking at this thread i backed out.

there is so much information to take into chosing the calipers and discs that i needed to educate myself and reading this and some other offsprings from this has helped much.

dandan
08-09-10, 17:15
Absolutely fantastic...

Might suggest taking the table out and moving it a new thread for reference and loose the chit-chat.

I'm happy for it to be moved/binned/adjusted - whatever will allow people to get some use from it. :)

I would still like to add in the info for the Whifbitz AP stuff when Paul has a chance to dig that out. It looks like the Jap spec also needs adding in plus there'll be Stoptech info from Luxluc and the K-Sport 356/356 kit info should be headed my way shortly from another member. :thumbs:

Do you want to move it first and if so, will I still be able to edit/replace the images it once it's moved?


Ill keep my eyes pealed. Ive always been a fan of alcons :cool:

Will keep you posted; I might do a little chat thread once I start the install/fabrication. Pads should arrive tomorrow :)


Great Job!

I would some info added if possible?

The j spec brakes and the Uk brakes in the big table thingy

because then newbies or people like me dont have to search the forum for dimension and weights and such.

since you have done such an awesome job so far maybe you can put it in pretty pls :-)

i almost had a setup of porsche gt2 brakes but after looking at this thread i backed out.

there is so much information to take into chosing the calipers and discs that i needed to educate myself and reading this and some other offsprings from this has helped much.

I don't have any info for the Jap spec stuff but I am more than happy to add it in once I have it...you're not the first person to ask.

I'm glad you found it useful and it potentially saved you some £££ and grief. :)

paul mac
08-09-10, 18:38
what a great thread Dan, this knackered shoulder of yours is really paying dividends for the forum mate :D

Wez
16-11-10, 14:11
Dan, any chance you could take a look at the AP CP6600 calipers and let me know your thoughts, it states they are for 330mm discs but I would be looking to use them with stock sized discs if possible which I believe are 323mm.

http://www.mkivsupras.co.uk/imports/2010/11/386.jpg

http://www.apracing.com/info/products.asp?product=CP6600+Family+-+130mm+Mounting+Centres+-+Suits+%D8330mm+Disc+_2760_2569

dandan
16-11-10, 20:33
what a great thread Dan, this knackered shoulder of yours is really paying dividends for the forum mate :D

Thanks Paul :D


Dan, any chance you could take a look at the AP CP6600 calipers and let me know your thoughts, it states they are for 330mm discs but I would be looking to use them with stock sized discs if possible which I believe are 323mm.

http://www.apracing.com/pics/productpics/cp6600_2.jpg

No problem at all mate, will get on it tomorrow.

Wez
16-11-10, 20:56
No problem at all mate, will get on it tomorrow.

Top stuff, thanks. I am wondering if I can up the disc size to 330mm and still get under my wheels.

dandan
17-11-10, 18:02
On the stock 323mm discs you'd be down by approx 13% on combined braking torque and the bias increases to the rear by 3%.

On a pair of 330mm discs you'd be down by approx 11% on combined braking torque and the bias increases to the rear by 2.5%.

In both cases I expect you'd be fine. On a track I assume you'll be running a race compound pad so you can easily make up for, and far surpass, the deficiencies in braking torque so they are irrelevant really. The main thing is the brake bias shifting to the rear slightly. I'm sure CW has his thoughts on how much extra rear bias a MKIV could take in track form (there's a whole heap of inputs and variables) but I suspect the 3% would be ok. :)

Wez
17-11-10, 20:26
On the stock 323mm discs you'd be down by approx 13% on combined braking torque and the bias increases to the rear by 3%.

On a pair of 330mm discs you'd be down by approx 11% on combined braking torque and the bias increases to the rear by 2.5%.

In both cases I expect you'd be fine. On a track I assume you'll be running a race compound pad so you can easily make up for, and far surpass, the deficiencies in braking torque so they are irrelevant really. The main thing is the brake bias shifting to the rear slightly. I'm sure CW has his thoughts on how much extra rear bias a MKIV could take in track form (there's a whole heap of inputs and variables) but I suspect the 3% would be ok. :)

Top stuff Dan, thanks :thumbs:

With these calipers I could move onto the Performance Friction 01 compound as currently I am using the 97, it was the only one available for the stock MKIV calipers, the 01 has a harder initial bite as the 97 is more of an endurance compound while still being very very good, by far the best pads I have used to date.

imi
17-11-10, 20:37
Basic comparison:

http://i828.photobucket.com/albums/zz202/danc8000/Supra%20Brake%20Comparison/412eafb2.jpg

Great thread, very informative.

could you add the UK Brake setup; I see the UK rears are included but not the UK fronts.

cyberdiamond
09-12-10, 03:51
Thank you Steve, I'll give it a go....looks like it might be a bit long winded though as my table is pretty big :)



That would be great Luc - I'm sure everyone would love to know how the Stoptech kit compares.Give me a shout when you're free to do a few measurements....the most awkward one is measuring the piston sizes (anywhere from 28-42mm in 2mm steps) but according to this info it can be done without taking the caliper off :)

http://www.zeckhausen.com/How_to_Measure_Pistons.htm

Luc/Dan How did this go?

I can add some more info as well as I currently have the StopTech 4 Piston front only kit installed and now have a StopTech 6 piston 355mm front and 4 piston 355mm rear kit being delivered.

j_jza80
17-03-15, 21:20
Just reviving this old thread to add a little more info. :)




198938




Dan, if you happen to spot this anytime soon, I would appreciate it if you could let me know how the LS400 calipers compare to the UK ones in terms of braking torque? The stock LS400 Discs are 315mm, and I don't think the LS400 calipers will fit over 323mm UK Discs.

Thanks. :)

Wez
17-03-15, 21:24
Its good to see the images are working again :thumbs: