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Just back from the dyno, comments on results welcome!


Mike B
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This is the first time I have had this car on the Dyno, I've had to make do with the bum dyno until now. We did 4 runs, the first three at low boost, and one at higher boost... it would be rude not to.

 

The first three runs were done at .95 bar just to check everything over, it was making 480 fwhp and 420 ft/lb.

 

Run 4 was 1.3 bar which made a respectable 538 fwhp and 473 ft/lb.

 

The noise of the thing on the dyno was impressive, even without a screamer pipe. I have a lot more understandling of how much noise insulation there is on the inside, and just how vilolent 500+ hp is from the outside.

 

For these runs I had a fresh tank of optimax, and water injection with a little meth, together with a set of cleaned and balanced injectors (the richest set furthest back in the engine).

 

A few points of discussion you can all help me with;

 

The Vpro / VVTi ecu FBW throttle setup all works as it should do! It's set up to detect det and shut down the throttle to protect the engine. Have a look at the power and AFR on run 2; power drops and afr's fluctuate downwards after 5000rpm. I was running optimum ingn advance and the cumulative heat buildup in the engine on run 2 caused det which the ecu picked up, shutting down the throttle :D. (All settings were the same for run 2 as run 1). You can see it as the afr's fluctuate towards the richer side of target.

There is a rotory dial next to the knock monitor which is linked to the ign map on the ecu. We pulled some ign and the third run shows everything nice and stable. Interestingly enough reducing the timing made little difference to power and torque was the same. This is one of the reasons I bought this car; it is self protecting.

 

Would you agree that the power curve is increadibly linear? it looks like an asprirated engine to me! quite different to most of the other dyno plots I have seen. Not sure I am am missing out on mid range punch, but it's very predicatble to drive.

 

I also noticed that the afrs are different under different loads. The ECU is self learning (to a target AFR) and as the car has not been used much lately you can see it learning through the first three runs, settling on a wot afr of around 11.5 for.95 bar. When you show it 1.3bar it is pushing the afr down to 10.7. Is this normal for most ecu's?

 

The EGT's were extremely low on the dyno. The highest we saw was 550 degrees, (bear in mind my sensor is in the post turbo, but the manifold, turbo and DP are all heat wrapped) which is much colder than I see on the road. In all honesty I can see more at a solid cruise at 80/90 - indicated 550-650 - where afr's are hovering between 13 on steady power, 14cruise and 15+ on light lift off. Maybe this is the W/I; idle = no heat buildup and as soon as I get .6bar climbing up the revs on the dyno wi comes on and stops temps rising?

 

Images; first chart is a summary of all 4 runs overlaid (power + torque), second is breakdown into power, torque, afr and boost, last is the injector report.

 

Having chatted to the guys they agreed in saying that balanced injectors are so important when tuning close to the det threshold; as my car has protection on it, and is running quite high advance, having a set of balanced injectors is very important. Even after cleaning there are some injector intolerances and the guys said that you would have a hard job finding a set of injectors that were all identical from new. It would be a case of testing 100 brand new ones to find 6 that were identical.

 

Lastly, is it a rule of thumb that ft/lb should be the same as FWHP, or ft/lb the same as RWHP? just want to check the accuracy of this dyno.

 

I could push the boost up higher but 1.3 sounds like a safe max for me.. the .96 turbine housing registers much higher on the bum dyno but I can't live with the shitty throttle response.

 

Suspension sorted care of CW in a month or so and I think this will be my finished car. :innocent:

 

all comments welcome :thumbs:

web 4 dyno.jpg

web 4 graph.jpg

web inj.jpg

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Very nice curves there Mike.. Would you say the gt4088r .68ar is brutal on the road... or progressive?

 

Did you do runs without the W/I....???

 

 

The injector tol's look good.. and I perfectly agree having a consistent spray pattern is very important... What is your fuel rail setup? Single or dual feed?

 

Find your egt's on the dyno a bit strange TBH mine have allways been consistent on the road and dyno..

 

How many -deg did u pull the timing on your 3rd run.. I've found a little retard i.e 2 to 3 -deg dosen't make that much difference in power..

 

We all know too much timing advance can actually lose power..

 

What ECU are you running.. Sounds like its seeing increased boost duty so on the safe side its richening up your WOT AFR's as a safety mechanism..

 

What is the Threshold specified on your ECU for rich and lean settings..

 

Does it have a correctivness percentage for rich and low targets?

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What ECU are you running.. Sounds like its seeing increased boost duty so on the safe side its richening up your WOT AFR's as a safety mechanism..

 

What is the Threshold specified on your ECU for rich and lean settings..

 

Does it have a correctivness percentage for rich and low targets?

 

I'd say HKS Vpro and A/F Knock amp ? - Oh, just checked Mike's profile :)

 

 

The Vpro / VVTi ecu FBW throttle setup all works as it should do! It's set up to detect det and shut down the throttle to protect the engine. Have a look at the power and AFR on run 2; power drops and afr's fluctuate downwards after 5000rpm. I was running optimum ingn advance and the cumulative heat buildup in the engine on run 2 caused det which the ecu picked up, shutting down the throttle :D. (All settings were the same for run 2 as run 1). You can see it as the afr's fluctuate towards the richer side of target.

There is a rotory dial next to the knock monitor which is linked to the ign map on the ecu.

 

I'd

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Very nice curves there Mike.. Would you say the gt4088r .68ar is brutal on the road... or progressive?

 

very progressive, but brutal on te upper end, yet it feeds power in so gradually that you don't notice it that much.

 

Did you do runs without the W/I....???

no, always with the w/i, the car ran for 12 months without w/i.

 

The injector tol's look good.. and I perfectly agree having a consistent spray pattern is very important... What is your fuel rail setup? Single or dual feed?

dual feed

 

Find your egt's on the dyno a bit strange TBH mine have allways been consistent on the road and dyno..yeah, i find it strange too!

 

How many -deg did u pull the timing on your 3rd run.. I've found a little retard i.e 2 to 3 -deg dosen't make that much difference in power..

3 degrees..

 

What ECU are you running..

HKS f-con Pro V, with knock and vvti controller

 

What is the Threshold specified on your ECU for rich and lean settings..

i'm not sure on the specifics of the map, It's all locked away where no-one but the mapper can see. Good old HKS...!

 

Does it have a correctivness percentage for rich and low targets?probably but it's all password protected, so you have to have the hks writer softwear, and the password to the original mappers softwear.

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Thanks for this write up Mike. I'll pass this onto the interpro guys as they have not come up trumps with the Map2 ecu (despite the greatest of valiant efforts) and have now removed that and the stock ecu and are currently rewiring the car with a standalone ECU (think it's rebadged link type). I know they are having to mod the FBW throttle so your experiences may well come in handy for them.

 

I have also gone down the GT4088R route with a .96 housing and though you mention that in the thread, your sig suggests a .68. I think your results are similar to what I'm hoping for and it will be interested to compare as mine should have the wiring finished this week and next week it will be mapped.

 

Any questions etc are best fielded to Jody (and I'll try to get him to join the thread) as you have lost me more than once in the thread but I'm hanging in on the just of what your discussing.

 

cheers again

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Thanks for this write up Mike. I'll pass this onto the interpro guys as they have not come up trumps with the Map2 ecu (despite the greatest of valiant efforts) and have now removed that and the stock ecu and are currently rewiring the car with a standalone ECU (think it's rebadged link type). I know they are having to mod the FBW throttle so your experiences may well come in handy for them.

The fbw can be a pain in the arse, many people remove it, but I like the fact it steps in to save the engine if something goes wrong, the can't keep it.

my fcon runs the engine and the stock ecu is still there controlling the throttle position and it's emergency shutdown.

 

I have also gone down the GT4088R route with a .96 housing and though you mention that in the thread, your sig suggests a .68. I think your results are similar to what I'm hoping for and it will be interested to compare as mine should have the wiring finished this week and next week it will be mapped.

 

I have a .68, .82 and .96 divided housing. so far I have tried the .68 and .96, and it's the .68 every day of the week. it has such better throttle response, as i still like to drive the car, rather than blast down dual carriageways. I want to try the .82 when I get some time to swap them over; Jamie P rated this one.

 

I'll not know every technical detail as Terry S built the car, but I know the basics. This setup has been replicated in a couple of other cars on the board.

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Looks very responsive Mike, the power is coming in early in the rev range. Did Terry dyno the car when it had the GT35R fitted?

 

I'm suprised that the GT40R doesn't seem to be making any more top end power in comparison to my smaller GT35R on mine (similar power at same boost level). What cams do you have fitted? I know Terry bought the HKS Valcon kit, but don't know if he'd fitted it before selling.

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I have an old dyno of Terrys from SRR which shows 547hp, its overlayed with my old setup.

 

It has got new cams in it, valcon and 264 ex, but terry did have it mapped for 1.8 bar, and when I spoke to Reg (the mapper) he mapped it on race and road fuel, so for sure he put race fuel in and a fair amount of boost for his showcase dyno plot I recon; hence I have to pull ign back a fair bit.

 

I also think it would make more with a bigger ar on the turbine, but at the expense of throttle response. I'm not that enamoured of the 4088r in this respect. if you want drivability you have to choke it a bit with the smaller housing. Still no drop off top end though; peaks at around 6.5k. The bum dyno definately registers more punch on the 4088 than the 35 regardless of housing.. and these figures are not off the same dyno.

 

I'd like to see the plot of CG's T04Z, and I'm wondering if the throttle response of the BL67's is as good as people say it is...

 

you can never say for sure until you try them I guess.

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Interestingly enough reducing the timing made little difference to power and torque was the same.

 

Cant see your car being anywhere near MBT of your engine so on the run before the air temps must have been higher or timing must have been pulled as normally pulling 2-3 loses about 10- 20bhp depending on Compression Ratio. Does your setup have a active knock setup aswell so it pulls timing if the knock sensors pick up any noise like the stock ecu as this would also explain why the power didn't change. But There are many variable that can effect it but i wouldN'T worry about it as sound like you have a nice little setup there. :)

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but i would worry about it as sound like you have a nice little setup there. :)

 

I hope that was a typo!!

 

Does your setup have a active knock setup aswell so it pulls timing if the knock sensors pick up any noise like the stock ecu as this would also explain why the power didn't change.

 

possibly. The Vpro and knock sensor may pull it back a bit, but perhaps not enough on the 2nd run.. when we manually dialled it back the stock ecu did not see any det whatsoever on run 3 and 4 and left the throttle alone.

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I was at motorscope last week and is a very nice setup they have. I actually maxed out their dyno with a t78 car we did :D

 

Your wheel and fly figures look good also not loosing like 22% through the transmission which i have seen on others.

 

Just so you can see mike i have overlayed your graph against a comparision table i run at SRR but tbh your graph would look alot like the others if was ran at SRR due to the gear which is used (4)and the ramp rate.

 

Richard uses a slow ramp rate which puts more load on the engine to make the power in earlier across the range, the only down side to this is things getting hotter (ie air temps) at the top end as is a long run.

 

This is why your power starts to level off after 5k as probably some timing was pulled with the air temps rising.

 

I believe this is the same with your dyno sheet Nic

 

image

 

Ryan

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Wow, thanks for doing that Ryan, I have learned something else new today!

 

That's very interesting, and makes sense as well.

 

Terry's chart on the 35R that wez referred to was SRR in 4th gear.

 

The bottom half of my curve looks very impressive overlaid against the SRR... take that wez my lad! :D but you still make more top end than me..:search: Ryan's explanation makes a lot of sense, Richard's runs were very long, you could barely hear the revs rising at any appreciable rate.

 

It has to be said that dynos seem to be good to tune and diagnose but comparisons between them (machine innacuracies aside) seem fraught with issues.

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The wheel power to engine power calculation seems a bit odd, it's like they just added about 80bhp onto the result. The low boost ones give a 20% multiplier to the wheel figure, but that doesn't tally with the higher boost one, it's still just 80bhp when it should be 90 if the %age drivetrain losses were consistent.

 

I find that odd as that'd give you a higher flywheel figure than you got, and you know dyno's ;)

 

-Ian

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Dastek Dyno's use a run down seq after each run to measure the drag and then work out the loses.

 

I exspect where the gearbox fluid got warmed up after the first run it didn't cause it to loose anymore power through the Transmission.

 

It has to be said that dynos seem to be good to tune and diagnose but comparisons between them (machine innacuracies aside) seem fraught with issues

 

End of day its a tool to get the best out of the car in a safe environment. Just a figure at end of day and if your happy with it on road then thats all the matters :)

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End of day its a tool to get the best out of the car in a safe environment. Just a figure at end of day and if your happy with it on road then thats all the matters :)

 

So true. The best thing for me was to see the stock FBW safety net actually working, and the datalogging which is not possible on the V-pro; really poor of them imho, on what is a good ecu.

 

looking forward to the day we get aftermarket VVT turbos.. perhaps we will have all moved on by then to the second hand v10 R8's or new toyotas.

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It has got new cams in it, valcon and 264 ex, but terry did have it mapped for 1.8 bar, and when I spoke to Reg (the mapper) he mapped it on race and road fuel, so for sure he put race fuel in and a fair amount of boost for his showcase dyno plot I recon; hence I have to pull ign back a fair bit.

 

Mike, I remember Terry saying he had a thicker head gasket fitted (2mm I think) so he could run higher boost on road fuel. I'm wondering if 1.3bar is a little conservative for the engine setup you have.

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Mike, I remember Terry saying he had a thicker head gasket fitted (2mm I think) so he could run higher boost on road fuel. I'm wondering if 1.3bar is a little conservative for the engine setup you have.

 

I didn't see the reciept in his file (he kept everything) and no listing of it in his spec, but for sure I know the mapper had the car up to 1.8 bar on race fuel with no issues as I talked to him about it directly, so she's ready to go. 650cc injectors should (as I understand) take me to 650hp, I also use higher fuel pressure and W/I.. plus I have the FBW control just in case, so you are probably right; I am being a coward!!! lol

 

If Reg ever comes over I will have a play, but until then I shall remain the respectful owner to the old girl :innocent:

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