Dynamic vs. static engine balance?
 

Novice engine builder Q here: I understand that you want to balance the weights of the parts in motion (ie rods, pistons...). Does dynamic balancing work best when played off balanced parts, or is it good enough to dynamic balance only? My machine shop will balance with crank, rods ,pistons, flywheel, and impellar for $90. From what I've heard this is most important for a high reving engine. I am building a daily driver (5000 RPM max) and am putting in a crank/rod set that I bought from a guy. I don't know if he balanced the weight of the rods, and am a little hesitant to remove them. Should I balance the weight of all rods and pistons and not get the dynamic balance? Or is the $90 worth it? Thanks!

Ben

I say go for it. You will also need to have the pressure plate, which are said to often be way off, balanced after the pieces you mentioned are done.

Mike

static balance should be preformed on the rods(big and small ends) and pistons before the assembly is dynamicly (spinning) balanced. you should do it even if you plan to stay below 5k.

OK, thanks! I'll weigh the rods and pistons and then do a dynamic balance.