Did a search nothing came up. I just picked up a ZC SOHC that has a flex plate on it, I'm going to mate it to an si tranny so I have to convert to a flywheel isn't that going to affect the rotational balance? Is there something else I should do to balance it? Do the crank pulleys differ between auto and manual on the EF?

 

as long as the flywheel is balanced, your fine. torque converters when filled with tranny fluid are heavier than a flywheel, and they bolt straight to the flexplate.

 

Cranks are the same.