Turbo Minis and gearboxes?
Turbo Mini Forums

Hi,

I am planning to build a turbo engine for my mini, running 10PSI of unmodulated boost, and perhaps a modified head to produce around 100BHP.

With an uprated X-pin diff, am I likely to still eat gearboxes? How many miles can I expect the gearbox to last before needing another rebuild?

Thanks

with that sort of power i would expect the gearbox to last quite some time as it is normally the diff pin which goes first, obviously with the cross pin you will solve this problem, i would just get a rebuild kit and make sure the bearings etc are all ok.

I will be using a freshly rebuilt gearbox

good call on the diff, my girlfriends diff pin went a few days ago and put a nice hole through the sump

KK - If you rebuild the box, replacing anything that looks dubious (layshaft, bearings, etc) then you'll have plenty of fun!
You might want to consider swapping a final drive ratio at the same time?

That will be my intention to put in a different final drive whilst I am there. this isn't going to be happening for qutie some time, but I was told I'd munch gearboxes because of the torque produced by turbos. I just wanted to see what you guys thought.

Also, I've had a look in the faq, and can't find alot of info on turbo minis? What parts are required and so on, can someone point me in the direction of some literature to read through?

Many thanks

Con

all info on this site is turbo related the search is the best thing to use

Beginners guide thing is handy

My gearbox has seen about 70000 kms, 50000 km with turbo engine. Boost at 10 psi, last 3 summers at 16 psi. I took it apart 20000 km ago, and had to reset laygear, idle gear and primary gear end floats. I also replaced the primary gear since the bushes on the old one were worn. It was s/h when I fitted it and had done unknown mileage (100000+ km).

To summarize, with freshly rebuilt box and good quality diff, with all tolerances correctly set, I would expect a lot of mileage.

Think you get the idea that you will be fine with a recondtioned box but i will just add that i ran my normally aspirated 1380 for 2 years (108bhp) with a standard recon gearbox, it was my everyday car and got plenty of abuse:) The only bit of wear was the diff pin, ok not as torquey as a turbo with similar power but cant see you will have any problems.

-MINI CLUBMAN 1380 TURBO-