Pistons question

I thought Cord pistons had 3 compression rings and 1 oil ring, these pistons have holes drilled for oil rings on the bottom two groves, that would be 2 oil rings??

Those are the right ones. I will have an excellent set of 8 used Bohnalite pistons for sale at Hershey RNG 16-17. I believe they are 30 over.

This is an original Nelson Bohnalite piston with the Invar strut. Look at the last picture. See the metal internal piece. At the bottom edge of that is the piston name maker and thats the Invar metal common for this age of piston. The rings would have been cast iron. If anything I have posted someone please correct it.I wont be offended.


Gary Parsons

here are the pistons I have. I think I understand what you guys are saying about the skirt but I wan to make sure with all of your knowledge. 

I equally agree with Jim - the metalergy may be better now, though nothing wrong with the old ones either.

Jim: you are 100% correct. When I said I would vote for the bohnalite pistons, I took for granted they were the full skirted later Pistons. I’ve never seen 30 over earlier pistons although they might exist.

Hi Robert, To answer your question, yes todays pistons have better metallury in them then the pistons from the 1930's. However the pistons from the 30's are still running today in many Cords and have a lot harder miles on them then anything we are doing with these cars today. So yes todays pistons (depending on who's pistons you are using) are better then the old ones, I don't think they are that much better to warrent spending the $1200 for a new set. 

The one provision is as long as you have the latter pistons not the earlier ones. I wouldn't use the earlier ones.
Jim

After lunch today with Randy, He showed me several different pistons with the Invar supports. The Cord pistons were the Nelson Bohnalite pistons. My thoughts are you have original NOS Cord pistons....


Gary Parsons

I would vote for the bohnalite pistons.

I bought a super charged engine that came with most everything to put it together. it has .30 over pistons that are new and are mark with the name Nelson Bohnalite on them. I looked that up and it says that the were made for cars in the 30's and 40's. It doesn't look like they and being made today so I think they are new old stock but was wondering if the pistons made today would be better. They seem to be high quality but maybe the materials used today may be better and last longer. Anyone use these pistons before and can tell if they are as good or better than what i can use today.

thank you
Robert L Hauser