I just finished up my t56 swap today, and as soon as i started my car i notised a bad vibration, i pretty posotive its coming from my flywheel. I got an aluminum flywheel from spec pn sc66a for 2piece rear main, its supposed to be balanced already. It had a weight on it, i took the weight off and 95% of the vibration went away does any one think it would be worth it to pull the trans back out and rotate the flywheel in a different position and see what happens? Anything helps

 

A bolt-on weight is for a 400 SBC (or 383 if balanced like a 400).

You're probably good to go. If you do take it apart again, a machine shop should be able to zero balance the flywheel, if a pre-86 350 is what you have.

 

Its a 92 crate 350 bf goodrich motor, its comming out soon for a 383 to go in its place in february or march, its not bad now with out the weight, still slight, i just dont want it to damage the input shaft bearing on the t56

 

Cool, it has a very slight vibration still not too bad, i just dont want the input shaft bearing on the t56 to get damaged and its a 92 crate 350 bf goodrich motor, its comming out for a 383 to take its place in february or march

 

I didnt realise thet first one posted sorry, my phone lost servise and said it was unable to complete

 

you bought the wrong flywheel you need a 0 balanced flywheel and that motor should be a 1 piece rear main seal if it's a 92

 

i know what it should be. I ran the casting number when i bought the car, its a 1992 crate 350 bf goodrich motor 2 piece rear main. Its basicly a pre 86 block with with 87 and up heads that the person i got my car from bought "new" in a magasine years ago. Its the only flywheel i could find for the lt1 clutch that has a 2 piece rear main and thats not steel.

 

The 2 piece rear main seal crate engines as "Goodwrench" or otherwise were produced long after 1985 when production vehicles stopped getting them. You're right; it's still considered an 85-down engine for short block parts and balancer / flywheel opions.

Because you still feel it has a vibration, if you take it apart again, having the flywheel neutral balanced to be sure is not a bad idea. Removal of the weight from the SC66a so it's neutral balanced is correct and also applies to their SC66 series in steel.

Fidanza also makes an aluminum conversion flywheel: https://www.thirdgen.org/forums/tran...-flywheel.html