sooner or later im going to rebiuld my motor but i want to put s5 internals in it and had read that you need to use the s5 counter weight. can you still use the s4 fly wheel and what else do you recommend for swapping the internals?

 

the flywheel and front counterweight need to match the rotors, so for example you can use any 86-88 flywheel with any 86-88 engine, but an s5 flywheel wont work due to the balance being different