[73T/A]

Originally Posted by PAUL K

That's good information. Pontiac Engineering sent heads to AFR, Crane and Mullins. They were original service RAIV heads. The AFR were the clear winners and they were too busy to supply heads for Pontiac, so with AFR blessing they had Diamond Elkins copy AFR's work. It forged a long relationship with Elkins and later they helped develop the Turbo Regal heads. I've had heads and blocks come through my shop that came from the Pontiac Engineering Department. They had all kinds of numbers stamped on them. A lot more than just four twos and four ones. They really liked X and /. I've also worked on Pontiac round port heads that were worked on by Crane, Mullins and Elkins. All of them have the company name stamped on the ends of the heads. NONE of them had pushrod tubes installed.

There's a paper floating around written by a Pontiac engineer that used the AFR/Elkins head on the Pontiac flow bench that suggests the pushrod tubes and the port design changes at the flange for the SD head. Both those changes are incorporated into the SD heads.

The Unicorn 1970 RASD head was cancelled long before your heads were cast. We have a knowledgeable member here saying all 197's were cast around the same time. If Russ wanted to work with a special head why would he go with a 197 head? Why not the improved 7F6 head? He would full well know a RAIV head or SD head would kick the crap out of a 197 head. We all know that and he had access to a crap ton more information than we do.

If he used one of the RASD Unicorn heads would we assume the wrong later dates were added just to confuse the issue? Unfortunately we have no pictures of your intake ports but we know your exhaust port exits have been hogged out much farther than anything Crane, AFR, Elkins or Mullins was doing back in the day.

If you actually go back and read my original post you will see that I never mentioned the year 1970 RASD cylinder head I don’t know were you came up with that.So no confusion on my end.
I would think that if one was developing the 455 SD head that the 1971 455 H.O. head would be a good one to use to get porting flow data.It has the same 111 cc combustion chamber as the 455 SD and the 71 455 H.O. 197 head has better exhaust flow than the 1972 7F6 head right of the bat.The 7F6 head has a restrictive exhaust port (information from page 47 Pontiac Engine Design & Blueprint Assembly book).Craig Hendrickson& Kern Osterstock.You say that the 7F6 head was a improved.In what area just curious.Also you mentioned that the heads being disused just have four 2’s and four 1’s.I guess you didn’t see the RUSS or work order numbers stamped that was mentioned.If you have some pictures of any of the numerous heads that came through from Pontiac engineering myself and others would love to see them for future reference.You mentioned about the exhaust ports on the 197 heads being discussed as all hogged out.I would think gasket matched but not much if any beyond that.I am using stock Ram Air Restoration exhaust manifolds with factory metal gaskets with no overhang in the ports.Also using a untouched factory 1971 455 H.O. intake using stock port Felpro 1233 gaskets.

[73T/A]

Here’s what I would call hogged out!

[73T/A]

Originally Posted by PAUL K

Really, I think it's more plausible these heads were done by these guys rather than a secret Pontiac back door operation..... JMHO

Interesting maybe another possibility.Good info.

[steve25]

Too bad they were made / gasket matched that big at the exh flange .
There’s no need for that at all and it only makes for reversion and delaying the cam from coming into its power band.

[PAUL K]

Originally Posted by 73T/A

If you actually go back and read my original post you will see that I never mentioned the year 1970 RASD cylinder head I don’t know were you came up with that.So no confusion on my end.
I would think that if one was developing the 455 SD head that the 1971 455 H.O. head would be a good one to use to get porting flow data.It has the same 111 cc combustion chamber as the 455 SD and the 71 455 H.O. 197 head has better exhaust flow than the 1972 7F6 head right of the bat.The 7F6 head has a restrictive exhaust port (information from page 47 Pontiac Engine Design & Blueprint Assembly book).Craig Hendrickson& Kern Osterstock.You say that the 7F6 head was a improved.In what area just curious.Also you mentioned that the heads being disused just have four 2’s and four 1’s.I guess you didn’t see the RUSS or work order numbers stamped that was mentioned.If you have some pictures of any of the numerous heads that came through from Pontiac engineering myself and others would love to see them for future reference.You mentioned about the exhaust ports on the 197 heads being discussed as all hogged out.I would think gasket matched but not much if any beyond that.I am using stock Ram Air Restoration exhaust manifolds with factory metal gaskets with no overhang in the ports.Also using a untouched factory 1971 455 H.O. intake using stock port Felpro 1233 gaskets.

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.

[73T/A]

Originally Posted by steve25

Too bad they were made / gasket matched that big at the exh flange .
There’s no need for that at all and it only makes for reversion and delaying the cam from coming into its power band.

Those particular Ram Air IV heads are not mine.Just a random picture of a Hogged out head!lol

[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.

[PAUL K]

Originally Posted by 73T/A

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.

Understood..... The 1233 is smaller than a factory SD-455 port. It is the correct size for a RAIV/HO port.

You seemed to think Russ Gee may have been involved with your heads. I suggested, it seems more likely RUSS racing heads were involved with your heads. They even spell RUSS the same way it's stamped on your heads.

[73T/A]

Originally Posted by PAUL K

Understood..... The 1233 is smaller than a factory SD-455 port. It is the correct size for a RAIV/HO port.

You seemed to think Russ Gee may have been involved with your heads. I suggested, it seems more likely RUSS racing heads were involved with your heads. They even spell RUSS the same way it's stamped on your heads.

That is good info that you found on Russ Barfield.👍I need to look up more info maybe some one out there has a known set ported by him with those similar stamping.The Russ Gee reference was just a another possibility since he was involved with engine development etc.If another set of heads surface that would answer the question.If you look at the specs on the Felpro 1233 gasket there is only .02 differences in the height.The Felpro 1233 is actually talller than the RA IV port.

[PAUL K]

Originally Posted by 73T/A

That is good info that you found on Russ Barfield.👍I need to look up more info maybe some one out there has a known set ported by him with those similar stamping.The Russ Gee reference was just a another possibility since he was involved with engine development etc.If another set of heads surface that would answer the question.If you look at the specs on the Felpro 1233 gasket there is only .02 differences in the height.The Felpro 1233 is actually talller than the RA IV port.

The 1233 works fine on the RAIV if all one wants to do is seal ports. If one likes to do chit wrong and trim gaskets it can be used on the SD455. The Fel-pro MS 90123 has the same dimensions as the factory RAIV gasket and it's a better choice. SCE offers the correct dimension gasket for the SD455, no need to trim or massage the bolt holes. But all the gaskets are missing the square forward corner the factory gaskets used.

You could look for RAV heads with RUSS stamped on them. I'd think he did more work with those and that might solve your mystery.

[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 the 3/8 rocker studs and such that were on the heads.In retrospect the 3/8 rocker studs aren’t much of a indicator in how the heads were used in the past do to the fact that they can be changed and swapped out with 7/16 versions in minutes.Do to the fact the heads were 31 years old when I acquired them it’s anybody’s guess.

You mentioned that the 197 heads with a date code of Dec 1970/Jan 1971 would not be used for testing etc due to lead time for the 1973 SD-455 head.It seams plausible to me that there would be enough time .Not necessarily my heads but heads with that date code in general.I never heard that the SD-455 program was turned over to production in the Dec 1970/Jan 1971 time frame.Are you referring to casting the cylinder heads.I have seen a SD-455 head dates of Oct 1972 and some with no dates stamped on them those are probably earlier yet.Im sure the SD-455 guys know.

[242177P]

Originally Posted by PAUL K

Not sure why RUSS would have his name stamped on the heads unless he was afraid of loosing them.

If it belonged to Russ Gee, wouldn't it be stamped GEE?

[73T/A]

Originally Posted by 242177P

If it belonged to Russ Gee, wouldn't it be stamped GEE?

Possibly.Russ Gee was one possibility.One of the other forum members mentioned Russ Barfield and he might be on to something.I think that Russ Barfield is a good possibility that he did the SD-455 type port work on those heads.Russ Barfield also worked for Harvey Crane at Crane Engineering before he opened his own shop according to one individual.Pontiac was sending heads out too various shops for port work.We probably don’t know everyone of them.I read were Russ Barfield did build some stout Pontiacs back in the day.Im pretty darn certain that the other stampings were put there from Pontiac engineering to identify each head individually.The font and size looks like what Pontiac would used.Also the location and how it is stamped.They look way more precise and the font does not match the other stampings.Russ is such a common name though probably every state has a Russ Automotive or machine shop etc.Now if it said Nunzi that would be easier.lol

[73T/A]

I just noticed that these particular 197 heads have all six exhaust bolt holes.Production factory 197 and 7F6 heads are missing two bolt holes on the outer exhaust flanges.1973 455-SD had all six bolt holes.We know that a machine shop can add those also.This is just another item that I noticed .

The reproduction Ram Air Restoration manifolds that I am using are there SD version according to the receipt from Paul Delfield.So I am using all the bolt holes.

[mgarblik]

Originally Posted by 73T/A

I mentioned the 3/8 rocker studs and such that were on the heads.In retrospect the 3/8 rocker studs aren’t much of a indicator in how the heads were used in the past do to the fact that they can be changed and swapped out with 7/16 versions in minutes.Do to the fact the heads were 31 years old when I acquired them it’s anybody’s guess.

You mentioned that the 197 heads with a date code of Dec 1970/Jan 1971 would not be used for testing etc due to lead time for the 1973 SD-455 head.It seams plausible to me that there would be enough time .Not necessarily my heads but heads with that date code in general.I never heard that the SD-455 program was turned over to production in the Dec 1970/Jan 1971 time frame.Are you referring to casting the cylinder heads.I have seen a SD-455 head dates of Oct 1972 and some with no dates stamped on them those are probably earlier yet.Im sure the SD-455 guys know.

You are so right about some of the mysteries that surround these engines. My early 73 SD-455 engine has NO casting numbers on the exhaust ports and NO date codes. Only the full part number on each head. It has "A" connecting rods in it so I feel safe saying it was a pretty early engine.

[johnta1]

Here's a sheet that SDBob has explaining the dyno tests they did back in 1971.

[73T/A]

Originally Posted by johnta1

Here's a sheet that SDBob has explaining the dyno tests they did back in 1971.

That’s very interesting.I never seen that one.👍

[steve25]

Here’s the rest of that 1971 factory Dyno session info as provided by Pete McCarthy in the 1996 Sept/ Oct issue of Pontiac Enthusiast magazine.

Test 1 and 2 would have been with the RA4 Cam without 1.65 rockers and with open exh.

The other 4 test with the M-7 Cam as Pete says in the article would have likely been the RA4 Cam but ground with a 100/110 lobe separation.

You 455 owners out there running tight lobe separation cams thru exh manifolds are missing a out on a lot as this test shows.

[73T/A]

Originally Posted by steve25

Here’s the rest of that 1971 factory Dyno session info as provided by Pete McCarthy in the 1996 Sept/ Oct issue of Pontiac Enthusiast magazine.

Test 1 and 2 would have been with the RA4 Cam without 1.65 rockers and with open exh.

The other 4 test with the M-7 Cam as Pete says in the article would have likely been the RA4 Cam but ground with a 100/110 lobe separation.

You 455 owners out there running tight lobe separation cams thru exh manifolds are missing a out on a lot as this test shows.

Good information 👍

[73T/A]

Originally Posted by mgarblik

You are so right about some of the mysteries that surround these engines. My early 73 SD-455 engine has NO casting numbers on the exhaust ports and NO date codes. Only the full part number on each head. It has "A" connecting rods in it so I feel safe saying it was a pretty early engine.

The 455-SD is definitely a unique engine.Even though it was produced in low numbers it’s a wonder that it even made it into production with upper management at Pontiac changing attitude toward performance and the federal regulations on the horizon.No other mfg had anything like it at the time.