Its not much flying time around here in SD with temps averaging 0F.

I got my engine (Franklin 6) apart trying to cure a vibration problem
(0.4 IPS) - not extreme but anoying. Is it OK to balance the crank in a
automobile machine shop or are there some tricky things about aircraft
cranks? I know automobile cranks go to 6000 rpm and my aircraft crank
only goes to about 2800. So auto shops should be able to do a more
precise job?