Hi,

Just trashed 5th gear on my 5 speed P1 gear box. Also 2nd gear wont engage properly any more.

Running roughly 500 BHP on a 2.5 litre engine

Wanted to know what my upgrade options are? Was lookign at PPG gearsets, but they only seem to cover gears 1-4 and are about £2K plus install.

What is involved in fitting a 6 speed box (eg prop, rear diff, anything else needed?) What could I expect to pay and any comments / recommendations?

 

OK -looks liek im going to get a 6 speed box fitted. £1800 for gearbox + prop + £500 for a suitable limited slip diff. Plus fitting.

 

Rich:
make sure you get the shifter too.
Also, you must have the right matching rear diff ratio to suit the gearbox.

Expert is David at Welcome to the API website

 

I second what Graham has said here. I looked into a 6 speeder a few months back with a veiw to doing it on the cheap. If your lucky you'll get a UK 6 speeder for £1400 but then have the hassle of fitting it and matching a rear diff. API will be a fair few hundred quid above this price but when you consider they wont supply you with a duff box and they will fit it expertly this is a bargain in my opinion. I'm still getting engine bits and money together at the moment for a high power build but when I do I shall certianly be calling APi for a 6 speeder.

 

worth talking to david at api either way, they have just done my ppg gearbox which is what i would chose for that kind of power as the ppg raitios would suit your power, more so than the six speed imho

 

The problem is that this customer has broken 5th gear and is not confident that another regular 5th gear is going to be any better.

PPG is only 1,2,3,4 and standard 5th. So whilst he would be Ok with the PPG, the problem of 5th remains. I recommended a 6 speeder and that is the advice that he has accepted.

As he is not doing 1/4 mile competition he will not suffer the 'extra gearchange ' that you have to make down the strip.

David APi

 

nb - Bob also pointed out that the Sti 4 fifth gear is much stronger than normal and I could have used that with the PPG, but I still decided to go to a 6 speed box.

 

Turned up at 8:30 am after a 2 hour drive, everything went as planned and the new 6 speed gearbox went in without issue. Also got flywheel skimmed to remove some heat cracking and my headers changed. Also a loose connection in powersteering that was leaking was fixed for free. Eventually left about 6:30 pm by the time everything was done. Nice facilities and everyone that worked on my car knew exactly what they were doing.

Booked it back in while I was there to get some DEFI gauges and some WhiteLine suspension components fitted.

Also considering an engine rebuild to get my heads ported / polished and CAMs swapped, and cylinder liners fitted so I can run higher boost.


I noticed a slight problem with the 6 speed gearbox though on the way home - it crunches in 4th. David said it will be replaced next time i'm in and they will cover cost of my Silkolene oil, etc.

All in all quite happy with the service.

 

Soz to jump in on this one but David, could you help me out..?

I've got a sti8 UK 6 speed that crunches in 5th and sometimes 3rd when pushing hard...its syncros I'm sure. I'm just about to purchase uprated group N mounts and need the whole lot sorting early next year including changing of the oil to recommended Castrol syntrax - how much do you think this will cost? Ref the mounts upgrade, it will be engine and box changing which I understand can be done without taking out the engine - thank god!

 

swisstonihasher; you have mail.

David

 

Email rec'd, thanks David...

 

Sent again to email address. just in case.

David

 

How long has your 5 speed box lasted with that amount of power?

Cheers Dougie

 

guessing not very long, options are failry simple i'd have thought,

straight cut ppg box (5 or 6 speed)
helical cut ppg box (5 or 6 speed)
6 speeder

 

o and heres what a ppg straight cut box sounds like mine from a few weeks ago


Video of Scooby crescent - Photobucket - Video and Image Hosting

 

the red mica bug?

 

I recon there were 3 or 4 with straight cuts in that lot!

 

i do like the noise they make...

 

Or was it the first stickered blue classic you see?

 

About 6 months. The P1 has a Jap spec. box so its a bit stronger than the UK ones.

I think 5th gear gets the most torque so I guess its not surprising.

 

6 Speed box that crunched in 4th now replaced by API and the new box seems all OK.

 

Cheers, I have decided to get a ppg kit on mine in about a month , so I hope it lasts till then.

Dougie