[d63howe]

What intake manifolds will allow one to use the original RA pans to work
on a 70 GTO?

['ol Pinion head]

The original '69 & '70-72 dual snorkel A-body aircleaners are 1/2" drop from carb flange mtg area to the bottom of the aircleaner assm. Factory aircleaners like the '70-74 Fomula RA aircleaners & regular Formula & T/A aircleaners are 1.5" drop.

The original cast iron 4bbl or 2 piece intake (RA4/455 HO) fit perfectly as they originally did. Where the OEM aircleaner fit problems will pop up, is if swapping to a much taller intake like a Performer RPM or Victor /where the carb mounting pad is much higher.

[b-man]

If I wanted to use all the Ram Air components I’d definitely be running a factory Quadrajet intake and carb to insure the best fitment and maintain an original look.

Is there some sort of aftermarket intake you have in mind?

Anything under 500 hp runs hard with a factory intake and carb so in most instances there’s no real need to go aftermarket.

[d63howe]

The engine has Edelbrock D-port heads on it. The performer rpm is
too tall. Trying to figure out if something else will work. Port are big
enough stock RA will not seal.

[tom s]

Holley street dominator

[b-man]

Get your hands on a reproduction Ram Air IV or 455 HO aluminum intake.

The ports are taller on those compared to an iron intake. If need be you could add weld at the tops of the runners where they meet the head.

The ports on a Holley Street Dominator or Chinese knockoff of one won’t likely have ports that are tall enough without welding.

[d63howe]

I have one of the repo RA IV intakes, initial trial looked like it would be
hard to make work. Looked at it some more today a little on the front
runners that would not leave much to seal well. So I am going to have
it built up a little there and believe that will work fine.
I went at this backward, not enough research up front. I knew the RPM
manifold was taller but not by as much as it is. The man who did the body,
paint and assembly on this has kept telling me I needed to go ahead and
put the RA stuff on it.

[b-man]

Unfortunately the Performer RPM is 1-1/4” taller than stock.

You might be able to get the reproduction RAIV intake to seal as is, as long as you have about 1/8” of sealing surface it should work.

[d63howe]

It is about that in a couple of spots. Primarily at the front runners on the intake.
I could try it, worst I would have to do is remove it again.
Probably giving up some power doing this but it is not a race car i guess. It's a
.030 400 block with a 4" Scat crank, Eagle rods,AutoTec pistons with the Edelbrock d-port heads, RA exhaust nabifolds.

[b-man]

You’re giving up little to nothing swapping intakes.

The exhaust manifolds are the main thing limiting performance, the intake is not much of a player here in my opinion.

[d63howe]

Probably so, don't know if it will ever see the track. That question was asked while my daughter was around and she was not much in favor of that!

[d63howe]

After the felpro gaskets came in, lined them up on the head trial fitted the
intake. Reworked the ports to line up with head better. Got it back together
and fired it today. Weather not nice enough that I want to take it to the
street yat.