G_Sleigh_STi

O.k lets set some benchmarks:

1. STI8 04 engine
2. Already running TSL Triple 3 performance pack (So the fuel pump, down pipe and full exhaust system is already upgraded and the car is running around 333bhp.
3. Budget for suggestions is limited to £5000-£7500

Restrictions on suggestions

1. I want to keep the turbo as small as possible to keep the lag as reduced as possible lower down the RPM range.

So the main question:

3. Is there a way to get this engine to around run at around 400 lb/ft torque

So whats the plan people? Different ways of doing it?

Neilo

nope, thats way above what the turbo can do i believe. need something bigger.

DuncanG

Keep the small turbo as a paper-weight and slap on a big turbo and maybe also a bigger engine to help spoolup. Easy.

Certainly possible with your budget but not with the stock turbo.

Also you want 400lbft over what power-band?

G_Sleigh_STi

O.k I have changed the restriction because ive been told that the standard turbo just aint good enough for that kinda power. So lets start from there

Over what power band. Basically at the moment it starts to hit high boost at around 3500rpm and it stays at high boost right around to around 6700rpm from what i can tell (NOT dyno'ed just from feeling)

I like how it reacts at the moment, i just want it to react harder through each gear.

Pavlo

there is a lot you can do, you could get 400ft-lb from the standard turbo, Grp N cars do this even with an inlet restrictor, but they do it with lots and lots of boost. The size of the turbo will limit the overall power, but 340hp at 4500rpm is about 400ft-lb. The problem with this is the torque will be dropping off rapidly and you will be slower on the road than a car with more power as you will be having to change gear so early as the torque dissapears.

If you want a nice wide powerband, 400ft-lb and 400hp, then a larger turbo, exhaust headers, injectors will go a long way, stay with an Ecutek solution for ECU and you shouldn't have to spend lots of money. With the right turbo, and possibly even some cams (Spec C cams would be nice!) then you could see the torque range extended much further up the RPM range (equals more power).

paul

G_Sleigh_STi

Yea i want to keep it a nice wide power band. I like what your saying. Any idea of cost relating to that without me going away and pricing all the bits up over the internet?

SO:

Spec C cams
Exhaust headers
Larger turbo
650cc Injectors?
Another ECUTEK remap

Sounds interesting

G_Sleigh_STi

This the kinda turbo we are looking at? SBR GT12 Bolt on 500HP rated Turbocharger

http://www.scoobymania.co.uk/performance_info.asp?c=4 ?

Pavlo

Something like that, but I would go for a smaller turbo, that turbo will surge badly on a 2.0 engine. I'm not sure the "perfect" turbo for a Subaru 2.0 is being sold right now.

I would also say that the cams should probably be done last, and perhaps see how you go without them first.

I would personally avoid the Megan headers, as you will most certainly blow an expansion joint within 12 months if you push as hard as you will probably do to get 400hp. The GT-Spec, Gruppe-s Or similar would be a good bet.

I would budget the following, prices are conservative.

Headers and up-pipe £600
Turbo £1500
Injectors £450
Remap £650
Cams + fitting £1200
Tweak of map for new Cams £250

You could perhaps think about the latest ITG carbon airbox and filter for around £500 if you're keen.

If someone comes up with a good hybrid version of the Sti twin scroll turbo, then doing something with that might be nice, but it's generally uncharted teritory.

Paul

G_Sleigh_STi

Right thats incredibly helpful! Thank you. So what turbo do you think on the market is actually a good choice at the moment for optimal performance at BHP/Torque around the level i am after?

Also can you all recommend where to get these items at good prices, ive checked like 6 online top scooby tuners and they dont seem to list any of the items we have been talking about.

Tim W

iTrader: (1)

Zen Performance
Lateral Performance
Scoobyclinic
BRD

Oh, and using the web to search out what they can really offer is pointless, you need to talk to them! Incidentally Zen is Pavlo

TonyBurns

iTrader: (3)

JDM twin scroll engine
Though it will be pushing the top end of the turbo for it, it is possible and i have seen it done.

Tony

Hol

iTrader: (1)

I have Bob Rawles ex development car. JDM STI 04 with Twin Scroll and equal length headers etc.

The aim for this car was to get the most out of it, with the standard Turbo, intercooler and Injectors.

The net result was 369BHP and 368ibs. Which is very nice

But that is about as far as you can go with remapping on the standard turbo.

TonyBurns

iTrader: (3)

Hol,

The car i saw was mapped by Richard Bulmer, 361bhp, 402lbs of torque, just a decat, JDM STi MY04, vf37 turbo, and you have to think that these cars were actually made to take this torque, thus the different headers etc, this is a completely different beast engine wise to a UK car, far better for tuning

Tony

Hol

iTrader: (1)

Tony,

That is impressive. (and upsetting at the same time ) Do you know who owned it?

Which Rolling Road?




Sorry to hijack your thread Mr Sleigh!

TonyBurns

iTrader: (3)

Hiya Hol,
Dont know the owner but it was mapped/run on Prosports rolling road.

Tony

G_Sleigh_STi

Thats alright.

Right this is kind of a girls question...

You know uprating the headers etc and everything spoken about ealier to get that kinda torque...

Do you lose the scooby burble?

marklemac

You can always get unequal headers from GT Spec or similar, to keep the burble.

Thats what I did.

TonyBurns

iTrader: (3)

Yes you loose the burble, but if you want more power, its the way to go
TBH i dont miss the burble, my car sounds much nicer than my old one alot like a rally car sounds now but the JDM engines have more than just the equal length headers to produce that power, 80% of the engine has been either re designed or parts changed, like the crank, which now has better oil feeds on, pistons are not forged now but hyperthe.... something metal which is stronger and lighter, plus the benefit of it doesnt expand as much under heat so you dont get oil loss , twin scroll turbo, completely different in its power delivery, much livier than a uk car in all aspects totally different beast

Tony

alanbell

iTrader: (6)

Tony , What headers are best for a sti 7 , equal or un ??? cheers, Alan,

G_Sleigh_STi

LOL @ TOny Burns

Well i got my Type UK now and i cant get insurance on an import at 21. It was hard enough on a type UK!

So lets keep it relevant

Is the lightened fly wheel worth it?

Adam M

the burblring sound comes mostly from the fact that they are cast and then from the unequal length.

The hks/gruppe S do retain it to some degree.

I wouldn't be disappointed with bob rawle's ex development car, numbers are numbers, it is how it goes on the road that will make the difference.

I would be keen to tryh some kind of special twin scroll if that exists. See what pavlo @ Zen or mark at lateral or Andy F can offer.

Their results from SSO, TOTB will show you what they are capable of, and the games just got more serious.

You already have one of them advising you on this thread. I would say that you would do well to listen.

TonyBurns

iTrader: (3)

You've confused me you are insured on a type uk, its been modified and yet they wont insure you on a car with less bhp? well TBH, the price your paying for the type UK with mods, you probably could have got a JDM STi without mods, and then mod it i was getting the same level of quotes on a type UK as a JDM, no difference in price, though i am a little older i think most other people are getting the same.
But back to the question... is the lightened fly wheel worth it? probably not.

Tony

Buck Satan

A friend gets 475lb-ft at 2800rpm on a vf37, 2.0ltr with a few mods, not bad eh?

Pavlo

group N rally car I assume.

will depend on rollers too, I would expect lower figures in the above examples when tested on a Dyno Dynamics or Dastek rolling road.

R19KET

And running a SH*T load of boost to get 475ftlbs @ 2800rpm.

Mark.

Hol

iTrader: (1)

Or twin engines

Talking headers, I bought Gruppe S to go with the 2.5 and 20G I was going to use on a UK. But then I bought the JDM instead. Anyway I know they keep the burble on tickover, low revs.

As stated earlier, as soon as someone brings out a good twin scroll hybrid, it should be quite easy to get over 400ibs. Ill certainly be second in the queue. (always good to let someone elase make any 'mistakes' first )

Buck Satan

Group N wouldn't get close to that figure, boost is 1.8bar.

R19KET

Well, there must be a bit more going on too, because 475ftlbs @ 2800rpm, on a 2.0lt, running 1.8bar, isn't very realistic.

Is it running nitrous ?

Mark.

TonyBurns

iTrader: (3)

Sounds like the sort of torque a Grp A car pushes out

Tony

Pavlo

a group A (don't you mean WRC?) uses more than 1.8 bar of boost to get that torque.

A group N car CAN get close to that figure, I beleive the HDC car was rollered with 468ft-lb of torque, but with the turbo running flat out. It's still no more than 260hp at that torque though, and the torque is falling away rapidly as soon as it peaks.

Paul