hi people would any body know what is the safest power limit on the sti 9 engines? isit true they can take 500bhp on the standard block EJ25 i think?

would any1 recommend buying an sti ra with a 2.5 litre conversion?

many thanks

 

I would be un-willing to run a standard engine at that level for long.... 450 is about it for safety.
Someone will be along any minute to say theirs is doing 550 bhp without problems !
Most people would build a forged bottom end to cope with 500+ for a decent life-span.

IMHO

DunxC

P.S. If it is 500 bhp look carefully at the transmission spec. to match that power output.
New-age cars with six speed boxes are able to take this, but not classics, need special gears etc.

 

std engine will do 400 ish
std engine with forged pistons will do 450 ish
std engine with forged pistons and rods will allow you to raise the rev limit which you might want to do with a short RA box
std engine plus liners if you are aiming over 500 lb/ft torque

All rough figures and you 'might' get away with more if mapped det free

 

thanks...wel basically i have seen a type ra sti 1996, that i assume is a version 2? anyhows it has a 2.5l block, which is running 340hp/380lbs of torque. the gear box has just gone, but the seller is getting it built again using sti internals. so my main question is do you reckon the newly built box will take that sort of torque...iknw its hard to predict but all rough ideas count? im not a harsh driver i love my cars. btw one more thing should be worried about the standard diff on the RA, will that sort of power cause it to fail? as i have heard they are robust.

 

gearbox will die again in a short period of time with that power/torque.

 

any ideas of a box that can take the power utha than spending big money on ppd box or quaife?

 

6 speed is the way forward!!

Also been told but dont quote me! the 06 onwards 5 speed that comes on the 2.5 wrx can handle circa 400ftlbs???

 

I've mapped 2 x MY06 2.5 WRX's up around the 400lbft level and both have eventually broken 3rd gear. One gets used on track a lot and the other had a missed shift but it still doesn't fill me with confidence I'm afraid.

Andy

 

its a version 3 sti RA, and yes the box will break if abused, its torque that kills boxes not bhp, 6 speeder or ppg straight / helical is the way to go if the car will be abused, the reason why its bieng built up using o.e. parts is to get it back on the road again and since im not intending to keep the car no point in spend ing the extra for ppg/6 speeder...

 

oh chukde...mere sher.

 

Kidhaaaa!!!!!

 

Oi Aji bhangra pohna upneh logga deh saat.....brrrr ratta tat tat.

wer in berkshire you from mundia?

 

You might get away with using a gearbox from a v5/6 sti, as they are the strongest out of the all the classics.

Banny

 

Typical desi. Get side tracked too easy.

ps glassi larni?

 

The standard 6sp box is one tough cookie..... it has taken all I can throw at it and more by many others.

You havent got a Newage I know, but anyone with a newage STi..... with the right clutch these transmissions can take all but the true monster conversions. But saying that I have yet to know anyone busting a 6sp box, unless they are REALLY brutal with the shifts.

 

Amen to that Shaun

Banny

 

chuk deh dholliaaa! glassi nuy....hor glassi.....slowly slowy lol.

wer u from bruv?

 

^^^^

WTF is happening on here tonight..?

 

sorry mate got side tracked, my key board aint workin properly

 

hes talking in punjabi...