my 8 is running standard bottom end, just under 400bhp (399.5bhp) that was at 1.65 bar peak and 1.5 held. It now runs 1.7 peak and holds 1.6 but I will be upping this soon.
This is also on the standard turbo with a small hotside (I can change the hotside very cheaply and quickly which will loose me some spool maybe 200rpm further up, however it will hold power better even though I have a relatively flat boost curve)

 

Tony you keep saying this but what is your opinion based on (facts etc?) Not having a pop I am generally interested, as when I was on here a lot when I had my scoob there were a lot of engines going pop more so than are reported on the mlr The first time I heard chocolate pistons was on here

 

Even the newage uk sti engine can be pushed to 450bhp on the standard bottom end, several cars on here are running that no problem. Classics did got pop a lot and that is were the myth of all Imprezas being unreliable stems from.

Banny

 

New age cars as Banny say's, have different rods, which were the weak spot on the classics (well lots of weak spots on the classics, rods being one, main end bearings being the other), the later twin scroll JDM cars have better cranks (drilled/nitrided for better oil distribution to the bearings), stronger rods, stronger engines in total, easily run 400+bhp with no issues, but you cannot compare classic JDM cars with newage JDM cars, Subaru really did their home work when they re engineered the engines due to the issues they had with the classics, now they are much stronger and the engines are far better oh the joys of twin scroll cars

Tony

 

There's a few hatch STi owners out there who might disagree?

JohnD

 

Not the JDM one though

Tony

 

Comparing STi and EVO. I have an 03 STi (UK) with a fair few mods inc. an MD321H, 3" Milltek etc. My son has an EVO IX also with a 3" Milltek and K&N cone but otherwise standard.
He recently had it re-mapped after fitting the exhaust and the power curve compared to mine, makes interesting reading! His standard turbo spools nearly 1000rpm quicker giving great torque at much lower revs than mine. Both torque and power curves climb so much earlier and peak just over what mine gives. All this on the same rollers and by the same mapper. Even considering the EVO is lower geared, on the motorway it will pull from below 70 in 6th with a real shove in the back that the STi could only dream of!
Before the EVO he had an STi PPP and even when the EVO was standard (FQ320) he reckoned it was like chalk and cheese!
At least it doesn't sound as good as mine!

JohnD

 

John, his car is twin scroll, you have no chance of keeping up with it as he provides the power lower down (same with the JDM STI scoobs from 2003 onwards), but that is the joy of twin scroll STI's pull from 16-1800 rpm, its great

Tony

 

I think it all comes down to preference at the end of the day, I like the sound of my scooby over an Evo and as people have said set up right they are as good as each other, the Evo appears to be easier to make more power but my opinion on the whole is that the scooby's will make better torque because of the flat four engine, the unequal manifold also aids in torque over the equal length.

Reliability wise LMS have an import STI version 7 that is running meths and over 420bhp / 350lbs used as a demo track car and daily which is still on standard internals adn going strong. .

 

. .

 

Here is my boost curve on the evo at 1.5 bar (wouldnt reach its peak that it gets on the road)


ignore the afrs on the road they are fine

 

Incorrect, the equal length headers improve torque over uneven length, hence why twin scroll cars can make 360/400lbs on the standard turbo yet a uk car would be pushed to make 350/350.

Tony

 

im running a 321t and i pick up about 1 bar by 3 - 3.2 K but full boost 1.7 bar about 3.7 - 3.9 all the way to redline

maybe less i havent really had the time to look down at the avcr

wouldnt mind running 2 bar but would defo have to uprate something

has anyone run 2bar on standard internals

 

tony if id knew this before i would have bought equal length headers

dont you lose the burble though (i dont hink i could lose the noise)

steve

 

V5 STi seems to have biggest record of blowing + the P1 of course which had similar engine ... doesn't really happen in other models.

TX.

 

They wouldn't run it for long

TX.

 

this is maf problem, nothing more... the mafs in v5 v6 and p1 and some uk model cars are extremely fragile

 

The MAF's are just a part of the problem, the Version 5 STI's were the first to be mapped for 100 ron fuel, we didnt have 100 ron fuel at the time, the version 4's were mapped for 97 ron fuel so you could happily run those on uk super unleaded, plus lack of knock correction and a very agressive map on the v5/p1 and the V6 cars didnt help the matter

Tony

 

The thing is though, an evo has great spool same as a twin scroll unit and much better legs at the end, Rob North told me how his ran out of power at the top.

The latter is open to debate, a stock evo engine is better built IMO, the boxtersetup just does not compute with me, on a track and under oil surge conditions, the boxter setup is flawed IMO.

 

Ok then as an example of the newer lumps.....Evo X........525bhp aft achieved on the standard bottom end...argument over.

 

oh and Tony, not sure if your aware of the RS variants of Evo's but they every bit as good as your fabled Spec C's....they are 1250kg out of the box, mechanical diffs, ti turbo wheels for ultra fast spool and were made for the sole intent of selling to the rally guys who basically turned them into what they wanted from the great base they already are.

I hear so much about Spec C this, Spec C that, everyone thinks an Evo is a tommy Mak or a fq300......not the case.

With just remap, exhaust, fuel pump, mine made 385/390 and was on full boost at around 3k rpm on the road and had the legs that the twin scroll units could only dream of.

 

Go to you tube and see you "fabled" rs get its a(RS) handed to it several times on the track by just standard subaru's (not even Spec C's )
Someone on here is running 550bhp on a standard Spec C bottom end, more than the evo x

Tony

 

Oh and the twin scroll units, on full boost 2800 rpm, lower than yours

Tony

 

Slightly O.T. if I floored my 03' WRX in 5th at 30mph it would literally take 3 minutes to hit 50mph lol, but the car will just about hit 70mph in 2nd gear!

I think gearing in the WRX is why STIs don't get a look in on longish straights.

 

Its probably the bigger turbo, more time for it to gain momentum, this is why twin scroll units are good, give you the pickup of a small turbo but with bigger turbo power

Tony

 

Yes, I was making a comparison of the two cars as they stand. In power delivery terms, the EVO wins hands down. The STi however, has that rather old fashioned and somewhat endearing turbo characteristic of "wait for it, it's nearly there, here it comes" that reminds me of the old RS Turbo's and Cossies!

JohnD

 

just to but in lol - 5th in a sti 6speed is like 4th in the wrx 5 speed, 6th is pretty much the same ratio as 5th in the speed.

 

Yup the ratio's are close, 6speed 5th is higher than a wrx's 4th, same with a wrx's 5th, the 6 speed's 6th is higher again but not by too much, biggest difference is that a wrx has more of a cruising box, the 6 speed is closer so you dont have any gaps in the power band that you can get with the wrx.

Tony

 

i find the 6 speed too much work, constantly changing gear, i prefer being able to make the most of the long 5 speed gears, which co-insides with prodrives test figures with not having to change gear as much, i reckon a wrx with the same power as a mild tuned sti would be quicker- i'll find out soon when i get the vf35 and pinks done on mine lol- i'll compare to my dads sti running about 320 so will be about the same power.

 

yeah the 6 speed might be too much work,but i gaurantee that when you wont more power (and you will)

that poxy 5 speed box will go bang and you will go for either a dog box or the cheaper option THE 6 SPEED which is overall a great box
also what you have to remember is that the sti can be tuned higher (using standard internals etc) thus needing a stronger box

imagine an newage sti with a 5 speed box