[4birds]

I used to use Genuine GM SD-455 intake gaskets on my 1972 455HO. Then when I could not get them anymore from the Pontiac dealer, I believe Victor used to make them for the SD too, but that ended. The Fel-Pro 1233's suck for the early cast 7F6 scalloped ports. The gasoline will cause THIS after a while. The blue Fel-Pro 90123/90205 gaskets have a steel core which keep them in alignment with the port.

I 've been doing what BWB said earlier since the 90's.
My 2 cents.

[sd7369]

Ames part # FN769AC. 72 HO and 73-74 SD. They have been selling them for over 5 years I believe. Didn't anyone bother to check forum host's website or catalog?

[4birds]

The $109 price is a factor for most of us. But when you absolutely want or need correct and original look and quality, Ames has them available.
.

[ponyakr]

Originally Posted by sd7369

Ames part # FN769AC. 72 HO and 73-74 SD. They have been selling them for over 5 years I believe. Didn't anyone bother to check forum host's website or catalog?

Wow ! $109 + shipping.

https://secure.amesperf.com/qilan/Se..._sub_rowid=623

But, I suppose anybody with enuff $$$$ to build a real '72 455HO car, can easily afford another hundred bucks or so, instead of cutting up 2 different sets of gaskets. After all, I've read time after time on this forum, "Do it right the first time" , and "Do it once. Do it right.", and other similar statements.

This brings up more questions.

(1) Does anybody know if Ames still has some of these gaskets, in stock ?

"...The blue Fel-Pro 90123/90205 gaskets have a steel core..."

(2) I haven't found any online info stating that those FP gaskets have a steel core. So, could somebody please post a link to this info ?

(3) Does this mean that the Ames gaskets, and all other gaskets ever made for the '72 455HO & all SD455's also had steel cores ?

(4) Is a steel core gasket absolutely a must have, for '72 455HO heads ?

(5) Will none of the gaskets that Butler sells work on a '72 455HO ? Has anybody ever asked Butler what the best gaskets were for these heads ? Since many say they are the #1 Pontiac guys, maybe they have some info on this subject.

[4birds]

Look at this picture I just took. Steel core 90205. I'd get a picture of the 90123 also, but it is sandwiched between the intake and 7F6 right now. Almost all other aftermarket gaskets are a composite material. Use whatever gasket or material you want. Just trying to help the original poster's question and best course of action with options and facts.
Feel free to look again at the picture in post #21 and see what CAN happen when a softer composite gasket is used with the EARLY cast scalloped 7F6 head. This won't happen when a steel core is used. IMO. We are only talking about 1972 7F6 455HO heads.

[ponyakr]

"...Use whatever gasket or material you want. Just trying to help the original poster's question and best course of action with options and facts..."

I don't need any intakes gaskets. I'm just trying to learn something. I don't know any other way to do that if I don't ask questions & search for info.

" Look at this picture I just took. Steel core 90205..."

Thanks for posting that pic. I've never seen a steel core intake gasket, and didn't know til today that they made any for Pontiac.

I searched for steel core intake gaskets on the Summit site. I found some for BBC engines right away. But, all the listings I've seen for the gaskets you mention make no mention of a steel core. That's why I asked for somebody to post a link to that info. If a Pontiac guy has never seen a steel core Pontiac intake gasket, nor any listing for any, how on earth is he supposed to know that one exists ? I suppose that just proves to most here, that I'm an idiot.

https://www.summitracing.com/parts/f...make/chevrolet

https://www.summitracing.com/parts/f...w/make/pontiac

"... the EARLY cast scalloped 7F6 head..."

OK, this brings up more dummy questions. Before today, I'd never heard the term "scalloped" used in connection with a Pontiac head. So, what's the difference in a head that is scalloped, & one that isn't ?

And, since you capitalized the word "EARLY", does that mean that only those 7F6 heads that were cast EARLY in the run were scalloped ? Exactly how do you tell the difference ?

Does that mean that there are SOME '72 455HO heads that can use regular type gaskets---just NOT the EARLY scalloped ones ?

Excuse my ignorance. But inquiring minds want to know.

Also, so I won't have to go back thru and search, has it been established that the OP's exhaust leak is definitely caused by having the wrong gaskets ? And, are his heads definitely the EARLY scalloped ones ?

['ol Pinion head]

"Early" original casting 7F6's were cast on a variety of dates in August, Sept, & I believe Oct of '71. These have the scallops (recessed areas) between the intake divider areas of the heads.

"Late" style original production 7F6's were at least cast in January & at least on one date in mid March of '72, no recesses. My late built '72 T/A has the A dated 7F6's. There are pics here on the site, though with PhotoBucket issues, may not be visible.

[ponyakr]

"...scallops (recessed areas) between the intake divider areas..."


OK, I just looked at some pics I have. I think I see what your're talkin about. The dividers between the intake ports are not even with the intake surface of the head. I never noticed that before.

So, that begs more questions. What was the purpose of this ? It appears to be intentionally made that way. And why did they quit casting 'em that way ?

There's no way a gasket could seal off the divider, to keep the intake ports separate. Right ? So, that little gap between the adjoining ports doesn't cause any flow problems ?

So, are the dividers even with the intake surface, on the later heads ? If so, does that mean that the metal core gaskets are not needed with the late heads ?

[PB]

Originally Posted by TA455HO

Original part number for these intake manifold gaskets was

485950 3.270 All 455 H.O GASKET, int. mfld. 2 1972 1972 3-14

There has only been one other time this part number has been mentioned on the entire PY Forums. Can you find when and what it was about?

Chad

.

I show GM part number 487079 as correct 72 HO intake gasket. I picked up this spare last year at a show. I used this part number gasket on my rebuild two years ago. Works great.

[TA455HO]

Both part numbers show nearly an identical listing. I think they must have had 2 possible part numbers for this.

487079 3.270 All 455 H.O GASKET PKG., int. mfld. (w/WD, WM, YB, eng.) 1 1972 1972 3-13

485950 3.270 All 455 H.O GASKET, int. mfld. (w/WD, WM, YB, YE 2 1972 1972 3-14

Chad

.

[TA455HO]

I had removed the picture from the hosting site but still had it on my phone so I re-uploaded it. See if this looks like correct shape to you.



Chad

.

[TA455HO]

I see what is different.

487079 is a kit that you have/had which included 2 gaskets and some other goodies. Only 1 kit needed per car.

485950 is simply the individual gaskets - one each to a package. Two of these needed per car.

Chad

.

[PB]

Cool Chad...thanks for the clarification! Yeah, now I remember they have little plastic rings in the package to line up the gasket too. Yup , those are right on the money. Too bad no one reproduces it correctly.