wrong spec submitted by MOPAR

[David Barton]

Originally Posted by Irv Johns

In my case there were no piston specs for the 392 till March of this year. My engine was built with Diamond pistons as per NHRA specified with NHRA Logo and Diamond pistons engraved on top (early Drag Pak pistons had no engraving on top that was added after the first ones went thru teardown). There was no part number or ring spec in book til this March. My engine builder only had what was available for specs last June when my engine was built. He trusted Diamond to build pistons per NHRA as they were a approved vendor.

We built a 392 last year but chose not to run it because there was no approved piston. We were told that if we ran a standard bore size it would have passed as a factory piston. But since we bored it out there was no way it would pass because there was no approved piston listed.