what power are the general boxes rated too and what are the prices of uprated ones, ive got a history of doing boxes down to my embarresing ham-fisted gearchanges

just wondering on options and what power there rated too aswell as the obvious price involved

cheers again, im sorry i keep askign questions but im serious about getting a scoobie and wanna get a good idea of what i need to make it similer power to my old t34 stage cossie holding 27psi

cheers

 

Try David at API Engines. They do stuff like this and can advise on power capabilities.

 

I smashed 2 WRX gearboxs running prob 250/250 but others have been running 400 on them, depends on the driver

But agree with the above any gearbox queries API is the place to go

 

David at API is the master but as a guidline found during my searches (I ended up at API too)
UK/WRX classic boxes tolerate about 300/330 lbft torque
Sti Ra/Sti classics tolerate about 350 to 370 lbft in V3 /V4 V5 V6 specs

To reliably tolerate 380 lbft +

1
Fit a 6 speed box/prop/rear diff for £2000 ish + fitting
2
Fit a ppg gearset and some fresh synchro's for about £3000 + fitting

The 6 speeder is bullet proof and much heavier than a 5 speeder and you have one more gear to change = lost speed
The 5 speed ppg is an ace piece of kit and available as a straight cut or helical cut synchro or dog engagement spec.

David on Welcome to the API website

 

Graham,

I thought the classic WRX boxes were the same as the STI? I know the ratios are different to the UK. Are they not a stronger box than the UK?

You have me thinking now as mine must be near 340 -350hp on its original box. MY98 WRX.

Wayne.

 

The Sti's, esp V5 on had additional heat treatment to toughen them up, that is why I went to the Type R for mine.
Remember my stock Sti V3 has run 380 x 370 for 3 years in hill climbing with ZERO problems.