Tuning A UK TT Supra

Can peeps please tell me if there are any downsides to tuning a UK TT Supra....

I have been looking to buy a Supra for a long time now and recently (Mostly Insurance) UK spec GZ's seem to be the way forward for me

anyways...

I know they have bigger breaks, Larger injectors, Steel turbos but is there a down side, For example do they have extra bits that get in the way when adding intercoolers, Single Turbo, ect ect ect

any infomation on this would be a great help!!!

No real downsides like you mention, only the MAF sensor when you go for big power, but that can be overcome with more £££

Only other thing is "bpu" doesnt really do much for a UK spec.

BPU doesn't do much for a UK-spec? It only raises the bhp from 326 to around 410+bhp that's all!

UK-specs are not GZ Supras by the way.... the GZ is the similar japanese spec to the UK versions. So there are still quite a few differences when it comes to tuning them.

sorry forgot to answer you initial question there....... obvious downsides to tuning a TT are the extra strain on turbo's and the rest of the drive train. The eventual money required when turbos and clutch and tyres get worn out at faster rates than usual.

Also if you are thinking of fitting a FMIC then if you go for an active front spoiler version then the motor mechanism gets in the way of all. Usually has to be taken out and spoiler either removed or left in the down position.

Do you have proof that bpu gets you to 410+? On UK fuel without turning the enginge into a grenade?

Do you have proof that bpu gets you to 410+? On UK fuel without turning the enginge into a grenade?

Do you have proof that it doesn't?

If mine is a good representation of the breed then yes.

With only 40k on the clock and everything running fine when I went BPU Id say it was.

IMO stock based turbos do not make a reliable 400+bhp everything just gets too hot.

I've got a BPU dyno plot for mine showing 417bhp, I've also got another showing 341bhp and another for 379bhp - evidence is in the eye of the beholder

I've no idea what I am in BPU land these days, BPU+ perhaps but I'm getting a healthy 380bhp at the hubs at 1.2 bar

Only 400bhp !!!! Theres a lot of pps would kill for 400hp !!

BPU according to the guy who coined the phrase is

Full decat, Exhaust, Fuel Cut Device and Boost Controller,

think 400+ hp isnt a prob and pretty safe on a uk tt,

ive had no probs with mine,

it'll be on a dyno v soon so will post results.

Can peeps please tell me if there are any downsides to tuning a UK TT Supra....

Your wallet gets empty very quickly buying all the goodies

I fitted a FMIC and had to loose the active spoiler. It no big deal as the FMIC was very worth while IMO. fuel economy is the only thing that I noticed suffer.

Yep FMIC on mine also and cant say i miss the active frnt now that the frnt bumper has been replaced for a slightly deeper wider job

still cant believe how much that active unit is.

bpu is definitely worth while on a uk car. it transformed my car completely. when going single the only real difference to a jspec is the maf sensor which can be removed with a MAP ECU or a VPC. i went for the latter option.

sorry im feeling a bit stupid today, whats a VPC?

BPU is exhaust/filter, fuel cut defencer and a boost controller. FMIC is BPU+

Another view could be that FMIC opens a whole new world of improvements by ditching the front/rear intercooler ducting and the front/rear coolant rad ducting as well.

Crippling of the active front spoiler is an extra bonus.

Preheating the air before passing through the condenser and coolant rad brings yet more *FREE* horsepower and reliability.

Not to mention the preheating effect of the cone air fitler 'systems' common in so-called BPU

[/devil's advocate]

Not wanting to get into a dyno result v dyno result debate, as that has been done elsewhere. I still believe that 1.2bar does not give the same benifits to a UK car as it does a J-spec.

I also know that at 1.2bar especially on stock turbos the EGTs can ride too close to what is acceptable.

As as side note, you dont need to remove the MAF sensor when going single, only if you want big power.

sorry im feeling a bit stupid today, whats a VPC?

its an electronic device made by hks which is now obsolete. it basically removes the maf sensor and uses its own map sensor. have a look on http://www.to4r.com . nearly half of them big power supes are using the vpc. i know its dated technology now but it works.i also have the accompanying hks gcc which is a very basic fuel controller which i'll probably swap for the apexi safc2 eventually

Hmm!! so do they cost more to tune over a J spec? and the MAF fingey-me-bob does it restrict how the car has to be tuned?

What ever car i get some day im hoping to have it running 550 - 600 bhp!!!

Some Day........

JohnK : are you saying that it all comes down to the strength of the turbos between the different cars? In that a J-spec at 1.2bar will be under lesser strain than a UK-spec at 1.2bar?

I've had my UK-spec 6-speed running at 1.2 to 1.25 bar for nearly two years without any problems on stock turbos. The car gets an oil change every 5000-6000 miles and the usual other general servicing items... and it's been fine from day one.

Is ceramic material in the J-spec turbos stronger/weaker/same strength as steel turbos in a uk-spec in terms of shear and yield strength?

I still believe that 1.2bar does not give the same benifits to a UK car as it does a J-spec.

Look at the times in the drag race section, for similar mods the J-spec cars in general get better performance.

I've had my UK-spec 6-speed running at 1.2 to 1.25 bar for nearly two years without any problems on stock turbos. The car gets an oil change every 5000-6000 miles and the usual other general servicing items... and it's been fine from day one.

Im not saying it wont be ok, just that when running 1.2bar things get hot, at times too hot, this can cause problems. On the hottest days of summer I could see over 950c with sustained WOT runs.

Is ceramic material in the J-spec turbos stronger/weaker/same strength as steel turbos in a uk-spec in terms of shear and yield strength?

I have no specific test data, however experience from club members show that ceramic turbos seem to fail before the steel versions when running higher boost.

Im not saying it wont be ok, just that when running 1.2bar things get hot, at times too hot, this can cause problems. On the hottest days of summer I could see over 950c with sustained WOT runs.

I have no specific test data, however experience from club members show that ceramic turbos seem to fail before the steel versions when running higher boost.

Think the failure of the ceramic turbo's is possibly down to the ceramic impeller being glued for want of a better word (bonded) onto the shaft thus high temps f**k with the glue, where as the uk's are friction welded onto the shaft, any takers ?

This if im right sort of implies that a uk car on stock turbos running higher boost should be less prone to turbo failure due to high egt's

as Dnk points out this would indeed suggest that the UK-spec turbos are stronger and would result in them being able to 'take' 1.2 bar more easily than a j-spec ?

but without proper test data and a comprehensive list of turbo failures at specific psi pressures then I think its all hypotherisation (it that a proper word or not?).

This is correct, they are stronger and more reliable at running higher boost. Just look at the US, what more data/history do you need.

John, UK times Kevin Huntleys old car was running about .2 of a sec slower than Matt Hardwoods which was one of the quicker J-specs to run in standard form but for psi and bpu bits and on normal tyres. Ratio of UK to jspecs are about way bias toward Jspec, so you're never gonna get a fair breakdown.