402/375 pistons

Jimmy70RSSS · 09-09-2024, 03:35 PM

I bought an old 402/375 iron head combo. Pulled it apart today and it has CP pistons C8-CP. The ring grooves and rings are thin. Is this legal? It?s definitely not the stock width ring grooves. No spacers were used.

ss3011 · 09-09-2024, 05:00 PM

Sounds like you have some Super Stock pistons. The real answer is the ring grooves

should probably be 5/64, 5/64 , and oil groove 3/16 .

Jimmy70RSSS · 09-09-2024, 05:22 PM

The part number is on the list of accepted pistons for stock eliminator. That?s why I was shocked to see the thin rings with no spacers.

1347 · 09-09-2024, 05:58 PM

Quote:

Originally Posted by Jimmy70RSSS

The part number is on the list of accepted pistons for stock eliminator. That?s why I was shocked to see the thin rings with no spacers.

Probably why looking at the top of the piston for an approved number in teardown may be deceiving.

09-09-2024, 03:35 PM	#1
Jimmy70RSSS Junior Member Join Date: Apr 2011 Posts: 7 Likes: 4 Liked 0 Times in 0 Posts	402/375 pistons I bought an old 402/375 iron head combo. Pulled it apart today and it has CP pistons C8-CP. The ring grooves and rings are thin. Is this legal? It?s definitely not the stock width ring grooves. No spacers were used.

09-09-2024, 05:00 PM	#2
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 900 Likes: 67 Liked 238 Times in 112 Posts	Re: 402/375 pistons Sounds like you have some Super Stock pistons. The real answer is the ring grooves should probably be 5/64, 5/64 , and oil groove 3/16 .

09-09-2024, 05:22 PM	#3
Jimmy70RSSS Junior Member Join Date: Apr 2011 Posts: 7 Likes: 4 Liked 0 Times in 0 Posts	Re: 402/375 pistons The part number is on the list of accepted pistons for stock eliminator. That?s why I was shocked to see the thin rings with no spacers.