[672brlbaby]

Trying to verify , either way, if the Ram Air manifolds will work on a 64 block in a 64 GTO. Have written to 2 places that sell them so far, 1 says it won't fit, 1 says it should fit. Figured I would ask those who have done it. Apologies if this has been discussed, I didn't find it. Thanks for your help.

Jim

[65 Lamnas]

The d-port style for the ‘67 GTO will fit. To verify they are the ‘67 style, both of the outlets should be 3 bolt flange.

And we are NOT talking long branch style here.

[Sirrotica]

Only 1 year were the early manifolds made that will fit in a 64 chassis.by Pontiac, 1967. RARE used to make the 67 HO manifolds that fit 64-67 chassis, but since the owner passed away earlier this year, and his children took over the business and moved it from Prescott AZ back to Illinois I have no idea if they have 67 HO/Ram Air manifolds in stock.

It is possible to use the later manifolds on the early chassis, but some pretty radical metal surgery needs done to the crossmember area under the engine to clear the headpipe flange. I've actually made the late manifolds fit the early chassis, but it isn't something I'd do to a nice car. In my signature pics the 67 GTO/Lemans clone dirt car has 70 manifolds on it, but that car was going to end up in a junkyard if I hadn't built in into a race car. This car was raced from 1975 through 1978. It did finally meet the crusher after an major on track accident.

After swapping to the 70 manifolds that car picked up enough power that you could feel the difference, so it was a worthwhile swap.

Hopefully my answer helps you out...........

[b-man]

I’ve actually done it.

The 1967 GTO HO/Ram Air manifolds fit no problem. The 1964-1967 chassis are essentially the same with some minor differences, none of which prevent those manifolds from working.

I used the RARE 1967 GTO reproduction manifolds on a 455 in my 1964 Tempest.

It doesn’t matter which V8 block is in the car, any V8 with D-port heads is a go with the 1967 GTO HO/Ram Air manifolds.

[672brlbaby]

Thanks for the replies guys. Since there won't be money to find the rare 67 manifolds, and there will be no butchering, and no headers, standard manifolds win. Cheers!

Jim

[65 Lamnas]

Originally Posted by 672brlbaby

Thanks for the replies guys. Since there won't be money to find the rare 67 manifolds, and there will be no butchering, and no headers, standard manifolds win. Cheers!

Jim

They aren’t all that rare, unless you’re looking for originals. They’ve been repopped for DECADES. So if you’re patient and are able to wait, you’ll likely be able to find a used set priced reasonably. Have you placed a want ad here on the forum? Not sure if Inline Tube has these in stock or not.

[unruhjonny]

Although I have the 'Pontiac Bible' (McCarthy's book) - maybe some here don't have it for referance;
I had though that the 67 RA manifolds were essentially the same castings used in 1968?

I know I have some earlier (not repop) castings hanging in my garage, but if my memory serves me, neither of them have a casting date code...

[SD455DJ]

Just FYI...here's a '66 GTO that had a '69 RAIV in it (from a '69 Firebird!) with '68.5 RAII GTO manifolds (found the engine and manifolds in a local junkyard back in the 70's). The previous owner (original) torched the driver side frame & crossmember to make the manifold fit...what a hack job!

Dennis

[unruhjonny]

Well, i guess that answers that!

i cannot imagine a time when you could find RA stuff in the scrapyard - that had to have been awesome.

[b-man]

Some of the first reproduction D-port HO exhaust manifolds were the 1967 version, the main reason being their universal fit on 1964-1972 A-body cars and likely all second-gen F-body cars as well.

Though not ‘correct’ for the ‘68 and up cars they do fit.

[Sirrotica]

Originally Posted by SD455DJ

Just FYI...here's a '66 GTO that had a '69 RAIV in it (from a '69 Firebird!) with '68.5 RAII GTO manifolds (found the engine and manifolds in a local junkyard back in the 70's). The previous owner (original) torched the driver side frame & crossmember to make the manifold fit...what a hack job!

Dennis

When I used 70 RA III D port manifolds on my 67 stock car, that is very similar of what the frame looked like after I got done using a gas axe (cutting torch) to make them fit. This was in 1975, long before RARE was ever thought of. At that particular time, the 67 manifolds were as scarce as hens teeth.

Being that the stock car was already headed to a scrapyard when I decided to make it into a race car, I had no worry about modifying the frame to fit the manifolds. The car also had a full roll cage with reinforcements ahead of the firewall, as well as in the trunk area. Cutting a notch in the area pictured had zero effect on frame flex with the cage reinforcing the entire car.

As I have said previously when discussions come up about using the later manifolds on an early chassis, I absolutely would not do this to a street car with out making some type of a fabricated patch to restore the frame integrity after modifying the frame to fit the late manifolds.

There have been people that have said you don't have to hack the frame when swapping in late manifolds into early chassis, but the real GM D port manifolds will need this frame section removed. I've never owned any reproduction manifolds, so possibly the dimensions aren't the same as GM manifolds I know Paul (RARE) had stated in his ads that his manifolds were exact reproductions using GM blueprints. However there are other aftermarket manifolds that make no claim that their parts are the same dimensions as the OEM manifolds. That may possibly be the exception that others talk about that late manifolds will fit an early chassis without substantial frame modification, but I do know that the OEM manifolds need help to fit.

Unless the reproduction D port are different dimensions than the original factory parts, they won't fit an early chassis without major surgery. Thanks Dennis for that picture, it illustrates exactly what I have said repeatedly on the forum. My old racecar went to the crusher about 1978-79 so I have only the one picture of it I use in my signature picture in victory lane.

Dennis do you know what happened to the 66 in your pictures, was it ever restored, parted out, etc.

[SD455DJ]

Brad, these pictures are from last summer (2024) when my brother Dan 'found' the car in a barn (true barn find!). The '69 Firebird RAIV engine actually was running the original '66 4-bbl intake and carb along with the original ST300 2-speed auto trans with a 3.23 Safe-t-track. Dan pulled the engine and sold the carcass to a friend who is now using it for yard-art.

Dennis

[Ss182]

Anybody know if they will fit the b body chassis? Want to put a set on my 64' GP thats getting a 455 with 62 heads. Thanks guys.

[SD455DJ]

Originally Posted by Ss182

Anybody know if they will fit the b body chassis? Want to put a set on my 64' GP thats getting a 455 with 62 heads. Thanks guys.

B-bodies used the long branch manifolds. The driver side central exhaust outlet is the reason A/F body RA manifolds won't work, however, the passenger side will fit.

Dennis

[Skip Fix]

I have not verified but Paul at RARE said their repop RAIV will fit early GTOs. I think originals do not and nedd some frame adjustment-although that looks kind of exessive!