Balancing!!!
 

I have a 92 RS LO3(305ci TBI) and i was wondering if the motor was internally or externally balanced... The reason i ask is because i'm putting a carburated 350ci motor in and i'm ready to have the internals balanced and i was wondering if i could use my flywheel and harmonic balancer on the LO3...(By the way...i replaced the harmonic balancer and flywheel on my LO3 when i bought the car a year ago so they are in great shape)...Thanks for the help

Yes you can use them, as long as the 350 you are putting in has the 86-up 1-piece rear main seal, like your 305 does. Balance is not an issue.

If your 350 is 85-back, or is one of certain GM "crate" motors, then they won't bolt up. Balance is not an issue there either.

Well my block is a 1975 350...2 peice rear main...So it wont work then???

Nope, the flywheel won't work.

Easiest thing to do is to get the flywheel for a 83-85 Camaro / Firebird 305 with a T-5. It will be the correct diameter, crank flange, and balance.

It's best to leave the flywheel out of the balancing picture altogether, as far as the engine is concerned. Have the engine neutral balanced. Then if you're worried about your flywheel being balanced, have it done separately, also to neutral balance. that way you don't have an engine and a flywheel that are somehow uniquely matched to each other, and different from every other engine and flywheel in the universe.

You can use the balancer though. Again, don't have the engine balanced to it, rather have it balanced to neutral by itself if you feel that it needs it.

Thanks for the help!