3800 series II top swap question

"More Boost"

Major Member
Feb 13, 2005
ok, I've recently read where a n/a flywheel has a smaller weight than the s/c flywheel. usually when that is the case the harmonic balancer is weighted diff aswell. my question is guys doing a top swap with s/c balancer, what has to be changed? if anything. please
I don't have an answer for you but if you find out more info on this I would interested. I am trying to mate either a NA or SC to a manual non GM trans and I am working with a camaro flywheel.
If you're worried about that kind of thing you can run a single belt pulley for the supercharger and not change the balancer. Otherwise, most people just run the L67 balancer and forget about the rest. Technically the engine would be a little off-balance, bur I've never even heard about any complaints of vibration. Also, changing the flexplate is probably only going to aggravate that issue. Keep in mind that there are people who also delete the balance shaft to run double roller timing chains on stock bottom ends without much of an issue. I say run the L67 balancer and send it.
Jon is correct. I've built a bunch of topswap setups (including 2 for myself), and there has been no issue running a s/c balancer on an n/a bottom end/flexplate. Same goes for disabling the balance shaft for a double roller timing chain on larger cam/valve spring setups. Thankfully, these engines were built like tanks, otherwise modding would cost twice as much.