Packard Forum Index » Modification Discussion

Does anyone know if 359 pistons will fit in a 356, if bored out? The pin height and rods will be the issue to getting the 359 pistons to fit on the 356 connecting rods. Has anyone tried this?

Thanks,
John R.

Dear John:

Not possible. The 359 bore is almost 1/8 inch larger (if my numbers are correct). The service limit is .045.

Bore size of a 356 is 3 1/2", and 3 9/16" for a 359.

(o[]o)

I guess the number I was looking at was for a .040 over piston which is closing in on 1/8 of an inch.

The 359 cylinders are 1/16" bigger than the 356, 3 1/2" vs 3 9/16". The 356 has the same cylinder spacing and can use the same head as a 359 (and others) so is the casting that much weaker on a 356 that you couldn't bore it a 1/16" over and use 359 pistons? I guess the water jacket could be closer or oil passages.

John R.