[69camarox]

was wondering if any one has ever seen or used aluminum ramair exhaust manifolds i bought a set at a swap meet. guy knows nothing about them they are brand new have 1967 #'s on them wondering if they will take the heat ? or are they going to melt ? no one i know has ever seen or heard of them b4??

[b-man]

For short-duration use like drag racing, they will work. Even then, they'll blow a few balls of molten aluminum out if you run them a little too long.

The only factory produced aluminum exhaust manifolds were made for the '62/'63 421 SD engines, again for drag racing only.

[Jack Gifford]

R.A.R.E. told me that they HAVE been successfully used on the street. I decided not to pursue it, but maybe you should call R.A.R.E. I'm guessing they may use a better alloy than was in the old SD headers.

[White Warrior]

I ran an original set of 62 SD aluminum exhaust manifolds on the street on my 421 62 GP for about 10 years and never melted anything. The important thing to watch is your air/fuel ratio. If you ran a litlle on the rich side,you should be fine but if you go lean,you could melt them.

[Pontirag]

What about some sort of ceramic reflective thermal coating on the inside? I've seen it on some aftermarket aluminium olds heads in a resent hot rod magazine article. It seams that coating deal brings the overheating/ temperature issue under control. why not coat the inside of aluminium exuast manifold runners?

[69camarox]

that is what i was sort of thinking of doing.

[tom s]

Paul suggests that you do ceramic coat alu exhaust both inside and out.Tom

[67 Lamnas]

Maybe about 14-15 years ago my buddy Mike Wasson (of Mike's Tripowers) became acquainted with Paul Delfeld (sp?) of RARE right after he started repopping ductile iron HO manifolds. Paul gave a set of aluminum manifolds to Mike to try on his '65 GTO. As I recall, they were either pre-production or prototypes, but NOT regular production. They did fine for awhile, but eventually started to melt.....and Mike sent them back. Mike's car at the time might have been jetted a wee bit on the lean side. (I think) Paul eventually went to production with an improved version (different aluminum alloy), and advertised them in Pontiac Enthusiast and HPP...you can look back over some old mags from the mid-nineties and see his ads promoting them....

Anyways, what you have may be an early set or production set..might want to call Paul @ RARE, describe what you have and get his opinion...he's a nice guy to deal with.....

[speedshopmike]

i would not coat the outside - the coating will hold heat in once it gets there.
do the insides, though.

[Ccass]

They were available in the early 90's. They were a very nice reproduction. However, the car had to be setup just perfect or else they would blow a hole right thru them. From a business standpoint, they had to be discontinued as you might imagine the warranty problems associated with them.