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To BPU or not to BPU?


ccssupra
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Hi Guys,

 

I have had my totally standard 85k mile 1994 Jspec TT Auto for a few months now, and I always told myself that I will keep it standard as Standard Supra's seem to be a bit thin on the ground and may be worth a bit in the future.

 

I have also had bad experiences with upgrading/tuning in the past, I had an S14 that had 2 engines in 2 months and that was not standard.

 

The Supra is easily the fastest car I have ever had, but you all know that you easily get use to speed, and forever want more.

 

If I were to BPU, I would do it properly, most likely with brand new parts just for piece of mind. I just want to know, what should be done to the car to "prepare" for the extra load? The car has been very well maintained always using TRD consumables etc, and I believe it to be in very good condition.

 

I was thinking of the following:

 

Decat Downpipe (leaving one cat in place for MOT and to prevent overboost)

Catback exhaust (which one I am unsure)

Front mount intercooler (as my side mount isn’t the best of condition)

Electronic Boost controller

Cooler Plugs

HKS FCD (Will this be needed if the first cat is still in place?)

Walbro Fuel pump (255?)

 

It also has a new radiator and all hoses etc seem to be in good condition, is there anything else I should think about before performing the upgrade?

 

Thanks :)

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I can take you for a ride in mine sometime mate...

as for the list you pretty much have it spot on other than you need both cats out and have a restrictor ring which prevents overboost unless yours is a UK spec

 

if you click on BPU it pretty much explains it all

 

If you have an auto you may want to look at auto gearbox cooler, SRD sell them for £100

Edited by supra_ufo (see edit history)
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Yes you need the fcd still and to prevent over boost you fit a Restrictor ring and take both cats out and yes that fuel pump is fine that'll see you around the 400bhp with the rest of the mods you listed

But yeah make sure everything else is good like when you change your plugs check the coil packs and the clips then just other usual things like leaks etc

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I can take you for a ride in mine sometime mate...

as for the list you pretty much have it spot on other than you need both cats out and have a restrictor ring which prevents overboost unless yours is a UK spec

 

if you click on BPU it pretty much explains it all

 

If you have an auto you may want to look at auto gearbox cooler, SRD sell them for £100

 

That would be awesome mate, never even seen a BPU Supra in person never mind being in one!

 

I did have a look at the page, but there wasnt anything noted that should be done/checked before the upgarde, i'm just being as careful as possible :)

 

Good shout on the auto cooler, I didnt think of that, I'll add it to the list.

 

Yes you need the fcd still and to prevent over boost you fit a Restrictor ring and take both cats out and yes that fuel pump is fine that'll see you around the 400bhp with the rest of the mods you listed

But yeah make sure everything else is good like when you change your plugs check the coil packs and the clips then just other usual things like leaks etc

 

Cool, could I not get away with leaving the first cat in place to keep the preassure down and for it to pass MOT? Or is it better as you said to go full decat with a restrictor ring, getting the cat put back in for MOT.

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I can take you for a ride in mine sometime mate...

as for the list you pretty much have it spot on other than you need both cats out and have a restrictor ring which prevents overboost unless yours is a UK spec

 

if you click on BPU it pretty much explains it all

 

If you have an auto you may want to look at auto gearbox cooler, SRD sell them for £100

 

whats that about UK spec and no RR? :confused:

 

 

apologies for the thread hijack

 

I would also say be wary BPU the supra turns it into a completely different car, the second turbo comes online with a proper thump at 4k when BPU'd possibly put the car into TTC mode if you do BPU it, even makes it almost economical on fuel :D

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whats that about UK spec and no RR? :confused:

 

 

apologies for the thread hijack

 

I would also say be wary BPU the supra turns it into a completely different car, the second turbo comes online with a proper thump at 4k when BPU'd possibly put the car into TTC mode if you do BPU it, even makes it almost economical on fuel :D

 

A UK spec does not require a Restrictor Ring as the wastegate *insert some technical shit here bla bla*

 

EDIT

UK/Euro/US (Export) spec:

To raise boost beyond the stock level the restrictive catalytic converters are removed, thus allowing the turbos to spin faster and produce more boost pressure. Different to the jspec, the export spec has a larger wastegate which can handle the increase in exhaust gasses.

Therefore boost pressure will be maintained at only slightly above stock levels, typically 0.85bar (12.3psi). In order to raise this further it is necessary to install a Boost controller to change the way in which the wastegate opens.

A restrictor ring is not required on the export spec

 

I had mine in TTC for awhile as my VSV was goosed. Now its in sequential and I love it more compared to TTC. I didnt get the chance to drive it more in seqential as the weather went tits up but in TTC in this bad weather you feel safer.

 

That would be awesome mate, never even seen a BPU Supra in person never mind being in one!

 

I did have a look at the page, but there wasnt anything noted that should be done/checked before the upgarde, i'm just being as careful as possible :)

 

Good shout on the auto cooler, I didnt think of that, I'll add it to the list.

 

 

 

Cool, could I not get away with leaving the first cat in place to keep the preassure down and for it to pass MOT? Or is it better as you said to go full decat with a restrictor ring, getting the cat put back in for MOT.

 

Drop me a PM with your # and at some point in life when I put the car back together I will pop over, it will be defo this month unless we get snowed in.

Edited by supra_ufo (see edit history)
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whats that about UK spec and no RR? :confused:

 

 

apologies for the thread hijack

 

I would also say be wary BPU the supra turns it into a completely different car, the second turbo comes online with a proper thump at 4k when BPU'd possibly put the car into TTC mode if you do BPU it, even makes it almost economical on fuel :D

 

And thats exactly why I want to BPU it, everyone says it transforms the car and it turns into a beast, I'm all for that :D

 

A UK spec does not require a Restrictor Ring as the wastegate *insert some technical $#@! here bla bla*

 

EDIT

UK/Euro/US (Export) spec:

To raise boost beyond the stock level the restrictive catalytic converters are removed, thus allowing the turbos to spin faster and produce more boost pressure. Different to the jspec, the export spec has a larger wastegate which can handle the increase in exhaust gasses.

Therefore boost pressure will be maintained at only slightly above stock levels, typically 0.85bar (12.3psi). In order to raise this further it is necessary to install a Boost controller to change the way in which the wastegate opens.

A restrictor ring is not required on the export spec

 

I had mine in TTC for awhile as my VSV was goosed. Now its in sequential and I love it more compared to TTC. I didnt get the chance to drive it more in seqential as the weather went tits up but in TTC in this bad weather you feel safer.

 

 

 

Drop me a PM with your # and at some point in life when I put the car back together I will pop over, it will be defo this month unless we get snowed in.

 

Will do bud, thanks for the offer :)

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Hi Guys,

 

I have had my totally standard 85k mile 1994 Jspec TT Auto for a few months now, and I always told myself that I will keep it standard as Standard Supra's seem to be a bit thin on the ground and may be worth a bit in the future.

 

I have also had bad experiences with upgrading/tuning in the past, I had an S14 that had 2 engines in 2 months and that was not standard.

 

The Supra is easily the fastest car I have ever had, but you all know that you easily get use to speed, and forever want more.

 

If I were to BPU, I would do it properly, most likely with brand new parts just for piece of mind. I just want to know, what should be done to the car to "prepare" for the extra load? The car has been very well maintained always using TRD consumables etc, and I believe it to be in very good condition.

 

I was thinking of the following:

 

Decat Downpipe (leaving one cat in place for MOT and to prevent overboost)

Catback exhaust (which one I am unsure)

Front mount intercooler (as my side mount isn’t the best of condition)

Electronic Boost controller

Cooler Plugs

HKS FCD (Will this be needed if the first cat is still in place?)

Walbro Fuel pump (255?)

 

It also has a new radiator and all hoses etc seem to be in good condition, is there anything else I should think about before performing the upgrade?

 

Thanks :)

 

I'd be having a look at the suspension and brakes before going bpu, even if you didn't i still would

unless its all been checked over and is fine.

A full geometry check/set up wouldn't go a miss either.

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I'd be having a look at the suspension and brakes before going bpu, even if you didn't i still would

unless its all been checked over and is fine.

A full geometry check/set up wouldn't go a miss either.

 

Very good advice, I'd add uk brakes to your list and CW fast road pads. Geo check is a must at least once a year if you're doing a few thousand miles a year.

 

Mine's a daily driver so geo twice a year, you would be surprised how out of shape it gets with our rubbish roads.

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Forgot to mention, it does have the bigger brakes with TRD pads (unsure on discs).

 

It also has open diff, worth going for LSD? It recently had 4 wheel laser alignment, or is a geometry check something additional to this? Just using Standard Toyota Bilsteins.

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Forgot to mention, it does have the bigger brakes with TRD pads (unsure on discs).

 

It also has open diff, worth going for LSD? It recently had 4 wheel laser alignment, or is a geometry check something additional to this? Just using Standard Toyota Bilsteins.

 

Regarding the brakes what state are they in ? If they're old calipers they could be in need

of referbing due to the outer seals degrading over the years and either splitting or getting

holes in them which lets dirt and moisture get to the piston bores causing the pistons to eventually

seize.

 

Have you got a printout for the geometry settings ?

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Regarding the brakes what state are they in ? If they're old calipers they could be in need

of referbing due to the outer seals degrading over the years and either splitting or getting

holes in them which lets dirt and moisture get to the piston bores causing the pistons to eventually

seize.

 

Have you got a printout for the geometry settings ?

 

I cant complain about the brakes at all, no noises and plenty of stopping power.

 

I do have a print out yes.

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I cant complain about the brakes at all, no noises and plenty of stopping power.

 

I do have a print out yes.

 

There won't be any noises, the seals can be split for some time before you have any idea

something is wrong, by then its too late and the caliper usually ends up needing to be stripped.

 

You can only tell with a visual inspection, remove pads, clean around each seal/piston with brake cleaner

and have a close look at the condition of the seal.

 

You can replace the outer seals before this happens and save a lot of time and hassle stripping and rebuilding

them.

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And then single it and unleash the devil himself;)

To the op BPU it and enjoy a different level of performance

 

Kind of cant wait now :)

 

There won't be any noises, the seals can be split for some time before you have any idea

something is wrong, by then its too late and the caliper usually ends up needing to be stripped.

 

You can only tell with a visual inspection, remove pads, clean around each seal/piston with brake cleaner

and have a close look at the condition of the seal.

 

You can replace the outer seals before this happens and save a lot of time and hassle stripping and rebuilding

them.

 

Ok, I will certainly give them a check, I know they were shimmed a few months ago.

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