Originally Posted by donwhit
Get you Dremel out.
You need to remove a little from the webbing under the pinion. Also, fit the aluminium cam to the motor and turn it as far as it will go for a big pinion. Note where it touches (and is stopping you turning any further) and file material away to make it turn further. You will need to do this in two places on the cam. I did this and managed to get a 37/72 combination with no problems.
Thanks for the replies, I may just try going to a smaller spur prior to using the dremel. Hopefully that will work, Is it just me or does that ratio seem like the car would be overgeared? Up until I purchased the dyno I was running a 29/72 combination and I was doing well, it seems like a huge jump to me... That why I was thinking that the numbers may be wrong somehow...
Also how does the RPM Factor work for the gearing? I was told by someone at the track that I should simply enter in the number that is on the bottom of the screen, says something like 47% at 13000 rpm i think so my rpm factor would be 47%? is that correct?