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Aluminum 6pack Intake Narrower?

PurpleBeeper

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I've always heard aluminum and iron 440 six pack intakes are the same except for the metal. You can buy paper gaskets for the intakes (69 I think) that "sandwich" the valley pan. I've never been able to fit the paper gaskets on my iron intake which makes me wonder.....are the aluminum ones slightly narrower or "milled" when compared to iron intakes???
 
they're supposed to be the same. paper gaskets shouldn't be used with either unless the manifold is machined for them. the newer aftermarket edelbrocks seem to be wider than the originals. I know I've had to machine them to get a good fit. '69 manifolds for the most part are cut the wrong angles on both sides and this is how the papers came about to patch a problem.
 
My take on the paper gaskets with the aluminum manifold was that the aluminum deforms a bit more than the cast iron when tightening the intake bolts, maybe also accounting for the aluminum vs iron expansion difference, therefore allowing for a better seal with the tray, manifold, and heads. I never saw any angle difference in any of mine compared to iron or other aluminum manifolds. I'd suspect that tolerance on the head angle was greater than on the Edelbrock manifold. Just my observation.
 
I have never been able to use the paper gaskets on either cast iron or aluminum intakes (both B and RB engines). I just figured that the paper gaskets were one of those things that were available 'just in case' they were needed.
 
My take on the paper gaskets with the aluminum manifold was that the aluminum deforms a bit more than the cast iron when tightening the intake bolts, maybe also accounting for the aluminum vs iron expansion difference, therefore allowing for a better seal with the tray, manifold, and heads. I never saw any angle difference in any of mine compared to iron or other aluminum manifolds. I'd suspect that tolerance on the head angle was greater than on the Edelbrock manifold. Just my observation.
i had an over the counter '69 intake that the angles were so bad I should have thrown the intake away. I had a factory '70 alum intake that was perfect. I've had two later repops that were so wide I couldn't bolt them down without thread interference at the bolt holes. all the '69 intakes are junk. people just don't know how to check them. there was a reason why people took them off.
 
i had an over the counter '69 intake that the angles were so bad I should have thrown the intake away. I had a factory '70 alum intake that was perfect. I've had two later repops that were so wide I couldn't bolt them down without thread interference at the bolt holes. all the '69 intakes are junk. people just don't know how to check them. there was a reason why people took them off.

I had both an original 69 1/2 manifold and a mid '70's aftermarket. I used these on several sets of heads that had been milled (both deck & intake side), so they may have been more accurate than "stock". I found there was more variability in the bolt hole location in the valley pans which could cause problems.
 
I had both an original 69 1/2 manifold and a mid '70's aftermarket. I used these on several sets of heads that had been milled (both deck & intake side), so they may have been more accurate than "stock". I found there was more variability in the bolt hole location in the valley pans which could cause problems.
my experience has been different; then and now. in my opinion, edelbrock couldn't make them right in '69 and still can't today.
 
Well thanks everyone...... I need a good machinist. My block was "supposedly" milled .040" due a a "very uneven deck height" 25 yrs. ago & the heads were milled some unknown amount... and intake face of the heads looks OEM. Since the motor was together I shaved .020" off the intake faces & the holes still don't line up like I'd like them to.
 
Well thanks everyone...... I need a good machinist. My block was "supposedly" milled .040" due a a "very uneven deck height" 25 yrs. ago & the heads were milled some unknown amount... and intake face of the heads looks OEM. Since the motor was together I shaved .020" off the intake faces & the holes still don't line up like I'd like them to.

Beeper, you may have hit on your problem. Milling the block deck lowers & narrows the intake spacing. If the deck surface of the block or head was milled without milling the appropriate amount from the intake face, things don't fit. I know that some shops took shortcuts without understanding the problems created.
 
Beeper, you may have hit on your problem. Milling the block deck lowers & narrows the intake spacing. If the deck surface of the block or head was milled without milling the appropriate amount from the intake face, things don't fit. I know that some shops took shortcuts without understanding the problems created.
I'm sure you're right. Wish i knew exactly what was taken off the block face of the heads. I believe there's a formula for block face vs intake face milling....but i can only guess....which is why i only shaved 0.020" off the intake manifold. It's easier to take more off than put it back on.
 
FYI "back in the day", we took it off the heads so the manifold could stay constant and be swapped to other motors or combinations. The Mopar Bible has the formula, or an experienced Mopar builder.
 
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