Originally Posted by topside
Is that an old KB piston # ? Sounds familiar.
I looked on their site, and their part #s have changed, so the current 4.280-bore 383 part is UEM-KB210-030.


Nope. 50+ year old Trw/Speedpro forged Pistons.

Compression will likely be pretty low.

I might have an old Speedpro catalog in the shop. I will look tomorrow.

Edit: now that I think about it, might be a Trw/Speedpro cast stock replacement piston. Flat top, no valve notch, terrible compression ht. Might get 8:1 probably less.

Last edited by GomangoCuda; 07/04/23 11:35 PM.
In theory, there is no difference between theory and practice. In practice, there is.