Sign in to follow this  
Jim Anselmo

41-48 vs. 49-54 pistons for 6 cylinder

Recommended Posts

Can anyone tell me if there is a difference in the pistons for the 1941 -1948 239 6-cylinder versus the 1949 - 1954 pistons for the 239 6-cylinder? If so would you know what the difference is?

Thanks,

Jim

Share this post


Link to post
Share on other sites

The Pontiac parts catalog indicates 1941-51 are the same and early 1952 is too if they have a set screw pin retainer (later 1952 had a snap ring pin retainer). Then 1953 and 54 are listed with a different part number from those. The connecting rods apparently changed to reflect the new design too. Hope this helps, Todd C

Share this post


Link to post
Share on other sites

The 'later' ('52-up) pistons can be used in '41 and later engines; the rods are the same. The later pistons are desirable and much stronger. They are aluminum

with 'full-floating'' pins vs. the earlier which are more prone to cracking / collapsing.

Edited by Bill Wilkerson (see edit history)

Share this post


Link to post
Share on other sites

if you are going to use aluminum pistons, make sure there is enough clearance, because pontiac straight eights and sixes with cast iron pistons could run with tighter clearances due to both block and pistons were both made from cast iron. aluminum pistons will expand at a faster rate. charles coker, 1953 pontiac tech advisor.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this