The 1st & 3rd pics, in post #309, seem to prove that the SD-455 T/A Stockers ran G/SA, in both '74, & at least at the beginning of '75.
Not long after that, the H&M Bird was running E/SA. So, at some point, NHRA gave the SD-455 a big hp hit.
Anybody know exactly when & how much ?
Anyhow, I still can't exactly understand how John Clegg's '73 SD-455 Formy could have run D/S, @ Indy '73, if that in fact did happen.
If anybody has answers to some of these questions, by all means, please post your info.
So far, I haven't been able to find any written evidence of the exact NHRA hp factors for Pontiac engines, back during those years. They were supposedly in the NHRA "Factor Finder" publication in '72 & '73, then in the Class Guide beginning in '74.
But, so far, I haven't located anybody with a copy of any of 'em, or any place online to check one out. Gotta be a few out there somewhere, maybe ?
