[BruceWilkie]

Just placed a new Fel-Pro RA4 intake gasket on my 6x head and noted alignment was close on left pair but off on right pair(center of gasket over port opening a tid and far right off as well). So... I checked my other head ... practically identical. A set of 4x's on the bench checked the same, and placing the gasket on a T1 intake also indicated the shift(but opposite of course). So I have to conclude the gasket set is at fault not the heads or myself.

Anyway, is there a better gasket to use for a template?

Anyone that can tell me what/where the port divider centerlines should be?

And relative to what for reference?(The edge of the 2 countersunk bolt holes?)

I'm relocating the intake pushrod holes btw and have already made them solid by drilling/tapping for 5/8 threaded rod.(sealed with 2 stroke case sealer) It will require offset lifters and offset shaft rockers but I can easily remove the pushrod buldge (beyond gasket width if I want).

Also, doing this offers the opportunity to drill the new pushrod holes where I need them. I can drill them closer to rocker stands for high ratio as well. It appears if I stay with stock id pushrod holes(1/2") moved over say 1/4", a bit of the new hole would be open on the side of the holes but not enough to affect anything as far as durability goes.(there's just open area there) It also gives thought to drilling holes just slightly bigger than the pushrods I decide to run and "slotted" to act as pushrod guides.

I'm also undertaking some drastic exhaust mods that should leave the head resembling a Mopar W8 exhaust port.

Final porting of these heads wont be done by me. And yeah, aftermarket heads could actually end up at similar cost. (and probably better intake flow numbers). The exhaust side could move a lot of fumes if this comes out right.(I've seen W8's over 275 on the exhaust with a 1.62 ex valve no pipe) Should fit my turbo plans quite well too. I'm doing this more for the challenge. Heads had torched out ex bolt holes that someone tried to re-tap(possibly on the car?) and messed them up badly. So far its mostly my own labor.

I'm taking pics as I go and when I'm near done I'll post a thread on them. Seen where people in the past cut back exhaust ports but very little documentation of actual results. My planned mods likely to get slightly into ex side water jackets but between flange design, good machining and 2 stroke case sealer I highly doubt any water leak issues. IreGTO65 started ex mods last year but I havent seen progress.
http://forums.maxperformanceinc.com/...d.php?t=647793 PICs he shows are far less cut than where I'll be going. My center and end head bolts will be at same height as two inner short bolts and exhaust ports will be above the bolts. Flange will angle up like the W8 Mopar.

Anyway, any help on the intake port dimension/location will be appreciated. Feel free to add thoughts on my mods too.

Bruce

[J.C.you]

Sounds like you are going to spend some big time hours on them. i would approach it alittle different. Strive to make the intake port as straight as possible with your target csa of the port opening. Then work from there.

[tc]

The 90205 std port gasket has the port dividers too far apart from each other to fit my 061 head correctly and are too close to each other to fit my RPM intake. Also the 1/2 " alignment hole for the orange buttons were too small in the gasket. The buttons would not go in.

So I do not know what gasket would be best. Just know they don't fit good. I have an old RA4 gasket from the early 80's I could dig out, but you might be best to just make the gasket openings fit the head and intake you are going to use. I can help you make the openings bigger or move alignment holes if you want.

[BruceWilkie]

Seeing that the left side of the gasket aligns well with 2 sets of heads(2 4x and 2 6x nearly identical) and an intake manifold I'm just going to modify this gasket set for template purposes. The odds of 5 seperate castings being off the same amount are slim. The bottom and top openings are oriented correctly. I will measure the right port pair centerlines on all 5 castings relative to the countersunk bolt hole and take the average. BTW mine are the new style Fel-Pro with the embossed rubber on one side.

J.C.you... It appears that opening the pushrod bulge to the gasket line straight down removes 3/16-1/4" there. That alone is a large gain of csa. Its possibly more csa than I can acheive as I get to the short turn and bowl area. However it certainly makes it easier to straighten the path from there. Last night I removed some casting flash on the outside of the runners. There is a thin area just around the pushrod bulge I have to keep an eye on but all 8 ports appear similar thickness there. It appears that I have enough room to raise the entry to 2.3" from the stock bottom of the port with little fear of getting too thin.(I'll start at 2.2 though) The exhaust side is going to take some good machining to make a suitable place to make a new head side exhaust flange(probably 1/2" plate) fit but the port itself will be far easier than trying to port a standard head. There are a few straight cuts I need to make before I can determine the best angle the port flange can be. The head bolt stagger somewhat complicates this. I'm striving for similarity to a Mopar w8 with as straight a shot out the exhaust as possible.

[rohrt]

I ended up cutting the gaskets so each side was three pieces. The center used the gasket that has the block offs and the ends use the RAIV felpro gasket (sorry don't have the part numbers handy). My engine builder suggested it. I would have never thought to cut them but it works pretty good. I can get the gasket perfectly lined up on the front because the cut off water crossover holds it in place. The exhaust crossover is held in place by the metal blocks that have the hi temp rtv. This only leaves the back gasket to wrestle with and the orange plastic retainers hold it pretty well. I just cut them strait down the center of the intake bolts holes on each side of the exhaust crossover.

[BruceWilkie]

Well I measured and found the centerlines of the port divides. Averaged them out and working from there. As my ports will end up slightly wider I'll modify a set of Mr Gasket 503G's. The FP1233's I'll save for a stock app.

Got one head scribed out this AM. Port opening will be at 2.20 x 1.25 just slightly wider than a RA4 gasket. Removing the pushrod bulge completely, gives me more csa than I might get through the bowl short turn areas. We will see. I'll take the velocity loss for the straight shot toward the valve.

[taff2]

Bruce, on my last combo with ported '69 no.16 d ports,I found it easier to cut my own intake gaskets from gasket paper and then glue them to the heads.
With my turbo combo with the bifurcated(siamesed) inlet ports I used the Mr Gasket paper gaskets cut to suit.

[bryansMtngto]

Check with Flatout. they got a few different Pontiac gaskets. They even have a set the made off my Modified E-heads they selling too.