I've done a lot of searching already. If I got an internally balanced rotating assembly such as maybe one of these http://www.cnc-motorsports.com/category.asp?CtgID=12006 , would I just have to have a shop machine the block and throw it in, then put on neutrally balanced flywheel and vibration damper myself? Or would the whole deal have to be balanced again by the shop? By the way, I want a quality NA setup that could take nitrous and last as an almost daily driver for 100K plus. The shortblocks from Comb. Motorsports or Scoggin Dickey would do, but I think I could get better parts and equal assembly for over $1000 less as long as I can find a quality machine shop.

 

Answer for first question; yes! Answer for second question; if it needs (RE)balancing, you did not get what you paid for.

 

id rather order an un-balanced rotating assembly, then you can give the machine shop the flywheel and damper, so they can balance everything together for the best possible setup. that way you arent just guessing that the parts came balanced ok, especially if youre planning on spinning high rpm or spraying it.

 

A good (internal) balance job does not balance the flywheel and (damper?) at the same time, as that of the reciprocating assembly. The flywheel is balanced, but after the fact. Therefore, the flywheel is balanced separately, and for good reason.