Hi guys, i am trying to find a shorter final drive (crown&pinion) for the R65 Midland gearbox or any compatible Rover part, but i can't find anything. Does anybody know sth about this? I believe this change would be even better than modding the engine, since the Midland ratios are sh@t. Waiting for your help

 

Here's a starting point:

www.mgmetrocup.co.uk/

Click on the 2009 Regs & check out page 7. There are also some links to some Rover/MG tuners who might be able to help you. Supposedly, the R65 in the Mk1 MG/Rover ZR105 had an alternate final drive of 4.29. The K series engined cars (1400cc 16-valve) used an R65 up to 2003. There are several versions of the R65 so you'll have to do some research. The regs mention there is a bolted & non bolted Crown wheel depending on the model..

A while back, MiniMania USA offered an Ultrik ltd slip (part# NMG1001)It was offered "with the final drive of your choice; 3.94 (OEM), 4.29 or 4.54" The last two required an alternate pinion.
They or MiniMania UK might be able to point you to a current source. Good luck & please let us know what you turn up!

 

Your information were really usefull, about the MG ZR 105. I have searched for all Rover models with the R65, but not the MGs The 4.29 of the MG is just fine i think, the 4.54 is a bit too much. The 4.29 is a good compensation for both performance and every day driving. To my calculations, it will be a little shorter than the facelift Cooper, with the Getrag gearbox!