[73T/A]

Originally Posted by PAUL K

I'm well aware you mentioned RUSS and a work order number. None of that indicates those numbers mentioned would have matched up with numbers from Pontiac Engineering. Only the twos and fours look like something they might've done.

The SD head was turned over to production about the time your heads were cast. There'd be zero time to send them to be ported, returned, evaluated and Dyno tested. I brought up the RASD head as that's the only 197 head made with an 87 CC chamber. You mentioned your heads were probably smaller than the measured 92cc . I figured if they're not milled 111 cc chambers the only other option is the RASD. Or am I missing something?

If your heads have been matched to a factory exhaust gasket, it's an optical illusion they look larger. If your intake ports match a 1233 gasket they're smaller than an SD455 intake port.

The 7F6 is a redesign casting made with a different casting process. It's more consistent, has better water jackets, has induction hardened seats, a short turn which will work better than a 197 head and possibly an over the counter IV head, for competition use. The exhaust is not a restriction what so ever compared to a 197 head. But regardless the engineering department knew a ported RAIV head kicked azz. They felt like the SD head was better than the IV head. I'm quite certain if Russ wanted to put his name on a pair of heads it would've been a top shelf head..... Not a modified 197 when he knew he had several better choices.

It seems more likely RUSS racing engines in Florida stamped their name and order number on those heads. Especially since they came from Florida and RUSS operated in that State. It'd also explain the 3/8 studs .... GM engineering was using the 7/16 RAIV parts on their dyno engines, it'd be likely Russ would've continued the practice.

I mentioned that these heads may have been purchased out of Florida.I don’t remember for sure it’s been 24 years ago.I never stated that these heads for sure came out of Pontiacs back door only the comment that the individual made during the purchase.I stated maybe they did or maybe somebody just had them ported.The Felpro 1233 does work on the 455 SD or 455 H.O. and Ram Air IV.People on this forum have used them on the 455 SD intake side.