Ive been doing research on balancing a motor. But i still dont really understand it. One of my close friends just got his motor balanced and I was wondering what kind of balance he really has now. He doesnt know much about it either, he just trusted what the machine shop owner told him. He used the stock rods, stock crank, stock flywheel (m6) and stock Balancer. however, he did get .40 forged pistons. I know the machine shop asked him for everything to get balanced all together. Does this mean mean he still has the stock lt1 balance? is he going to be able to swap the balancer and flywheel without issues?

 

He needs to find out if it was internally or externally balanced. External is with the flywheel. Sounds like external since the machine shop asked for the flywheel.

 

i dont recall much, but i think it was external. Reason being that the machine shop asked for the flywheel, rings, pistons, rods, crank, bearings, and balancer. So was he supposed to get it internally balanced? will he be able to change the clutch and flywheel or balancer/dampner without having to take out everything again for balancing?

 

Stock cranks are intenally balanced at the front, but externally balanced at the rear.
A stock crank CAN be internally balanced, but you will add several slugs of mallory ($50-100 each).
At that point, you had might as well have put the money into a forged crank and paid to balance it instead.

FWIW; We put 5 slugs into a stock crank in my friend's 355. Plus the $175 to balance.
We balanced my forged crank for $175, no mallory added.

To properly balance a crank, you should provide the shop with at least one (preferably all 8)
rod/piston/ring set and the flywheel/flexplate that will be used. Providing the hub and
crank pulley is not mandatory and fluid-style dampers should never be run when checking balance.

The shop will provide you with a balance card that looks something like this
http://i38.photobucket.com/albums/e1...ild/img219.jpg