what gearbox and clutch are recommended for 400+ bhp?

 

Sti v5/6 box+diff and exedy organic clutch with lightened flywheel

 

cheers, im after info on whats the best route to getting my car suitable for 400+ bhp

i no bolting a load of stuff on under the bonnet and playing with the chip can get me there

but i want to be able the stop and send it round a corner

 

"but i want to be able the stop and send it round a corner "

????????

 

Is the box from an STi 5/6 different from the uk 99/00 ?

Phase 11 ??

 

Your best off with a 6 speed unit and rear diff, they are stronger than the 5 speed (though the selectors on the UK cars can be iffy except the 02 ones which are meant to have brass selectors rather than plastic ones).
You will also need a rear diff, cost about 2k for both.

Tony

 

TBH mate, i would stretch to a 6 speed i destroyed my 5 speed with 300bhp and 425ft lb of torque (2.5 conversion) but a 6 bolt 5 speed (99-00) would be up to the job for a while at least.

 

i mean i need to get the brakes, suspension etc sorted before i go and nearly double the bhp of my car, plus i want to make sure the rest of the car can handle the power, clutch gearbox etc

so i was asking whats the best route to start at

there is no point in being fast in a straight line if you need to slam on 5 seconds before the corner because the brakes cant slow me down in time!

 

Think you said it all there Andy. Its all down to personal preference i reckon. You can do a bit of each at a time to complement the other or sort out the brakes/sus completely 1st, then box, then the worlds your oyster with the engine......

 

Didn`t realise they could take that kind of power,,,,

 

Graham(911)'s been running that for some time now......

 

True, but i think he`s had a few issues too.

 

Dont think any of them were related to gearbox failure though....that i'm aware of...

 

I'm running a UK six speed and will soon be throwing 500+ bhp at it hopefully

 

I have been running 550bhp through a uk 6 speed for a few months now,with no problems

 

Anyone ?

 

The internals are hardened over a UK box and you will need a different rear diff to run one correctly.

Tony

 

Cheers Tony

 

It's "torque" that will break gears, which is why 2.0lt cars with "400bhp +", often get away with , because they still have relatively low torque.

Chriso2.5's example is good, 300bhp, but 425ftlbs.

Andy,

400bhp "+", just how much is the "+" ?


Mark.

 

They cant really, as on a 2ltr you are normally looking a +/- 10% square power/torque figures. (so 400bhp would be: 400bhp/360-440Ibs)

As Mark says torque (as a force) is the killer to a box.


That is not to say that some people have not run ver5/6 boxes with more than 350ibs going through them, but it is probably down to the mechanical sympathy they have for their car. (As well as the way the power comes in and the waer in the box itself).

 

My gearbox gave up at 350lbs ft so cut out the middle man and went for PPG which can take some big power , now running at 420+bhp/450lbs ft all day long and PPG just at you if you got cash go for it

 

I have been running 405 bhp / 360 ft lb through a P1 (Sti5) box now for 2 years without any problems at all.

I have done a few track days, but i don't do Johnny boy traffic light burn up's on the road, although i do drive it quite hard i suppose.

If you want to be sure of reliability, i would go with a 6 speeder or a 5 speed PPG kit though.