News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

boring the 322 39 lasalle engine--has anyone gone .125 oversize on the pistons?

Started by bariman, February 01, 2012, 09:08:59 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

bariman

Can you help me please?  I need to have my 39 Lasalle 322 engine bored at least .040 over and have heard some people say you can use Cadillac 3.5" pistons which would mean boring my block .125.  Does anyone have actual experience doing this??  Are the rumors true?

Thank you.

Fred Pennington 25635

I faced the same dilemma, Your machine shop should know someone who can sonic test the cylinder wall thickness. Racers who require very high horse power do this all the time to get the thickest blocks they can to reduce flex. Once you know the actual thickness you can make an informed decision on your block.
Good luck

Fred P.
Fred Pennington, CLC 25635
1940, LaSalle 5019
1940 LaSalle 5019 parts car
1968 Ford Bronco
1973 Mustang Convertible
2012 Shelby GT500

Bob Schuman

Dennis,
The original engine in my 1940 LaSalle was bored to use Cadillac 3-1/2" pistons, and has been driven several thousand troublefree miles since then. That may not hold true for each individual block, so it would be advisable to have the cylinder wall thickness tested before boring.

The LaSalle and Cadillac V-8 from 1937 on, used the same crankshaft, and rods. The lighter LaSalle pistons were compensated for, by using piston pins with a smaller lengthwise hole, so that the total weight of piston and pin was exactly the same as the Cadillac 346 engine.
Bob Schuman,CLC#254
Bob Schuman, CLC#254
2017 CT6-unsatisfactory (repurchased by GM)
2023 XT5