i have a internally balanced 400 sbc and need to know what flywheel i need to bolt it up to my stock t5 cause i don't have the money for the new clutch and tranny yet.

 

You need a stock T-5 flywheel. If you're sure it's internally balanced...

 

10 .5 inch diamiter .

 

yeah but i don't think that my stock 305 has a 2 piece rear main does it??

 

No, but a pre-86 one does.

 

so then a stock 305 t5 flywheel won't work for my 400 sbc cause it's pre 86

 

I think what Apeiron is saying is that pre-'86 engines use the 2 piece rear seal (like mine did). So if you find a pre-86 T-5 flywheel it will fit. Mine did.

 

400s are not internally balanced unless specifically modified to be so.

An 85 L69 flywheel is fine, but you need an additional balance plate that bolts between the flywheel and crank if it is a "normal" externally balanced 400."

 

- Then you don't need any counterweight.