browsing Alta's site you will find a Lightweight CrankPulley
http://www.altaminiperformance.com/p...ankpulley.html

anyone tried this? Equivelant to 100lb drop in the car seems worth $150 to me, after the pulley anyway.

 

This might be a good upgrade since you are reducing rotating mass. I have the exact formula somewhere but for a six to eight inch diameter rotating engine part, one pound of rotating mass is something like eight pounds of static weight. The ratio changes with the diameter of the mass and the way the weight is biased on the mass. The Classic A-Series engines had a harmonic balancer built into the pulley so you had to be careful when changing them because the wrong pulley would cause non-harmonic vibrations and possibly cause the crank to develop cracks! I don't think this is a problem with our MINIs, though.

 

Just installed the Alta crank pulley yersterday - and it feels a bit quicker.

 

how was the install? i have no idea where this thing even is. How long did it take? any tutorials?

 

This thread should answer juat about all your questions.

https://www.northamericanmotoring.co...ad.php?t=35290