burt2000

iTrader: (1)

Is anyone on the site chancing they're arm and running a 2.5 STI bottom end on a classic with the standard gearbox.

in the future i plan to go 2.5 with standard heads on a MY99 turbo 2000. I have the VF35, STI tmic, apexi power fc,FPR,decat downpipe and magnex etc on it at the minute....i had planned to upgrade the injectors to 550 and stick with the VF35 as a i really like how it drives. I would be uprating the clutch also

question is what sort of torque figures could i expect, id say max bhp would be around 350 but would torque be any higher as i know thats the transmission killer.

any thoughts or experiences would be great

andy97

iTrader: (1)

I had 380*380 wih my 2.5 conversion on a standard gearbox, but I was always aware that it could let go at any moment, fortunately it didnt, but there again I didnt ragged it very often. PPG or 6speed gearbox will ensure a robust setup.

burt2000

iTrader: (1)

what all mods did u have with that set up andy? in terms of clutch, turbo, injectors and engine internals?...380/380 would be really quick im sure!.....i dont rag that car hard either which would prob help longevity and i could budget for an upgraded box in the meantime

turboDean

iTrader: (4)

The VF35 wouldn't drive the same on a 2.5 as it does on a 2.0, it would spool much earlier and run out of puff in the top end of the rev range, it would probably drive very similar to a 2.0 with a TD04.

Its torque that kills the boxs and anything over 330lbs/ft and ur really pushing ur luck, there are plenty of people who have broke standard 5 speeds with 2.0's and VF turbos, a 2.5 with the same turbo will make more torque.

burt2000

iTrader: (1)

so something like a TD05 18g then would prob be better suited to it?

andy97

iTrader: (1)

At the time 2.5 with forged pistons, exedy organic clutch, 740 inj, turbo- 20G apexi fc

Now, PPG with Md321T and Simtek, somewhere in the early 400s for both.

I have a donor STI car to take it to the next step with nitrous, but that will be when this engine lets go.

burt2000

iTrader: (1)

i think a standard 2.5 with an 18g and 550's would do me otherwise ill be running into big money and then it gets to the stage were its better to go all out!

h4rry

iTrader: (3)

Im running over 400bhp on a newage and still have a standard wrx box if it helps, view my scoob for full spec. I am fully aware it could go at any point but the car has also been mapped in caution of this gearbox, i.e. its limited to 5500rpm in 1st gear so i cannot really launch it and i have a wide boost band in each gear so the power is not so sudden.

Planning to go 6 speed as the car seems really uncomfortable cruising at 70-80 mph and feels like it needs another gear.

Bez300

iTrader: (2)

good to see some one else with std 5 speed
glad it still in 1 box and not all over the road
my next step is 6 speed

Bez

burt2000

iTrader: (1)

thats a pretty impressive spec harry it most go like stink with that power, im wondering though do newage WRX's have a different gearbox to a MY99 classic, maybe the newages are a bit stronger......i suppose 380/360 would make for a very fast classic and as u say i could have it mapped so that all the boost isnt coming in at once .....must start saving now lol

j16jrf

iTrader: (3)

burt i went for the ppg option with mine. looked at the 6 speeds, but the weight of them put me off.

they are pricey but well worth it in the long run

Badbird

we have a stock dccd 5 speed I have been told this is a standard box as far as gearsets/syncro's go I have 400/430 at present View my Scooby the box hasnt got any worse in 2000 miles and i can tell you on private ground my son has launched it off the launch controll (simtek ECU) and iv caught him drifting it round the yard (Concrete not mud) no problem although one day it will be abused too far
think its down to how you drive them

mit

iTrader: (10)

It's a bit risky,seems to be about luck! I did the 2.5 on my old 95 uk turbo,killed two boxes with it,was only running 320/320. I think driving style makes a big difference,but whats the point doing the conversion and not using it?

stevie1982

iTrader: (16)

I am with MIT what is th epoint of spending all the money to get big power, larger turbo, 2.5ltr conversion, launch controll and then not using it as you are too scared incase you kill the box.

if you go for a 2.5ltr go a little further and do the box to
just my opinion

Badbird

AS I said the car is abused not driven silly on the street but i have acess to a large transport yard the car has neen launched off the launch controll often, Its been drifted round the yard which is concrete with plenty of grip donuts at every oppertunity we have activly tried to break the box, we want to break it on account of how the're not ment to live behind a 2.5 we have budgetted for a new box but in buggerd if i'll get one till i f**k this one

fygtbug

I'm on my second box in 10 months gone to a uk my98 6aa for the longer gears this time seems pretty good

Badbird

this story takes a twist
in trying f**kin hard to destroy my box, giving it the full bollox for as long as possible we broke the motor.....sodding box is still fine,
another rebuild
Damn

impreza_terzo3_no257

still ruunning a standard uk turbo box, done 27k on it and not missed a beat all about luck i think, I'll be going for the 6spd box and diffs soon.

2.5STI

how much should a 6 speed cost all in.