21 stud piston rings

fresnoron

Member
have 37 21 stud motor with 3 ring aluminum domed pistons 30 over. looking for rings for these. everything I can find shows second ring to have expansion ring underneath, but my pistons have standard style first and second rings with 3 piece bottom ring. I have found some rings marked 81A-6149-D2, but not sure if these will work. Can anyone give me a part number or supplier for the correct rings. also are all 85 hp motors 21 stud or are some 24 studs 85 as well. I am new to flathead motors so looking for information thanks all
 
The 81A prefix rings will work, but you're really better off to purchase modern rings from someone like Grant piston Rings. Do a google.
 
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When your asking about 85hp engines, are you asking if there was 221 ci 24 stud engines? This is a yes. Ford 221ci 24 stud from mid 1938 ish, the 1939 Merc got the 239 ci in 1939. This was an optional size on commercial vehicles, aswell as, but very rare, special order option on Ford cars.
After the war 239 ci was standard across the fleet till the 255 ci Merc only engine from 1949.
Martin.
 
I have spent three days on the computer trying to find Grant or Hastings piston rings for my 37 engine. I cannot find 3 ring configured for a non bored block. I just need standard size, 3 1/16" bore.

Does anyone sell them? Speedway's are all for over-bore, and Jegs, Summit,and the rest don't appear to have them. Nothing on eBay either, unless I'm missing something.

Any help greatly appreciated.
 
Read post #3 deep and shallow sets.
they will sell you phone them.

R

Yes, I know. I read that. I was looking for some place I could have ordered them from over the weekend.. We have already hot tanked everything and I'm running behind. I will call Hastings in the morning.

Thank you for your help, Ronnie.
 
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