1936 Buick 320 Pistons

I have 2 bad pistons. I just want to replace them and all rings. Bore is at least 5 thousandths wear. Engine was running great. Engine had a bad head gasket and when I was replacing head gasket when I found that top of 2 piston were damage long ago. Terrills machine shop does not list 36 pistons. I would like to change all the pistons if I could. Terrill machine do not have 1936 pistons. Do they interchange with other years? What is the difference?

Bobs Automobilia has them. 805 434 2963 or Egge.

Bobs Automobilia has them. 805 434 2963 or Egge.

Terrells has 8 pistons w pins for 1938 up 320ci for $260. Less than half of what egge and others charge. What is the difference between the rods that I cannot use 1938 pistons?

Are you assuming that the difference is in the rods and not the pistons? I ask this because I'm not certain but thought the difference is in the pistons and primarily the top of the pistons. I know that the original pistons for a 36 are flat top and I believe that this is also true for the 37. I also thought that rods were the same for 36-49 320 cui excepting the conversion from babbitt to inserts.

I also know that the original pistons for a 38 are "domed," referred to as turbulator. Now, the big question is whether or not the 38 pistons will fit into a 36 or 37. The bore is the same but I do not know about the valve clearance. I believe that this is the big question and it seems that I recall a forum discussion on this a couple years back but I cannot find it. I believe that you have the opportunity to save some money if someone who's been there before can steer you in the right direction.

Ok, I searched the pre-war forum using search words 320 pistons and found two discussions that pretty much said that the 38 pistons will work on 36 & 37 - although there wasn't that really valuable followup that we'd all like to see. Egge has the 38 pistons and for some reason, I can't get on Bob's website and haven't for a few days now.

This may or may not be of help, but the original pistons for 36, 37, and 38 (maybe even later but not certain) had a top ring that is 5/32" thick. The replacement pistons had a top ring that is 3/32" thick. It is not easy to find original standard ring sets that have the thicker top ring.

If you go for the 38 pistons, let us know how it worked out.

Joel