Aluminum/copper header gaskets -anyone make their own?

I'm running Clifford "shorty " headers on my 235 Chevy six, with a 2-bolt outlet. The conventional header/manifold composition (over a steel core) gaskets only last for a couple of years before the composition burns away, so I'm thinking about making my own.

I work in aircraft and the softest aluminum we use is 2219-0. Will this work if I aneal the material or should I look for some copper sheet to try? I won't need much, as the outlets are only 1-3/4". What about brass material? I'm thinking around .030-.040" thick might work by my guesstimate, but will go thicker if i can find it.

Has anyone here made metallic gaskets for exhaust systems and have any tips to pass on, as for material, thickness, or DYI heat treating?

Mucho Thanks, Tim

 

exhaust gaskets usually fail when bolts are loose try tighten them up once in a while

 

Have you tried different brands? I'm surprised better quality gaskets aren't available.
lht has a good point. Old straight six engines have a bad habit of loosening up their carburetor and manifold bolts. You get in the habit of checking them from time to time, as when doing an oil change or tuneup. I don't know if there is any Loctite or other cure that will stand up to exhaust heat.

That is the next question, what about exhaust heat? Will aluminum stand it without burning up? Copper might but copper is also harder.

I know when cars were first invented they tried copper gaskets, which lasted but didn't seal well, and asbestos which is soft but blows out easy. The final answer turned out to be sheet asbestos wrapped in thin copper which is more or less how they make them now only with thin steel and some asbestos substitute.

So, maybe OEM quality gaskets and new unworn OEM quality bolts, checked for tightness a couple of times a year.

 

Give it a go.
I made some copper ones for my pontiac 400" engine to suit the header flanges. I think it was about 1/16" thick, easy to cut with a little bench scrollsaw and then anealled. Never had a leak for 5 years and they get really hot. I guess a head gasket would be harder to cut, my mate got a copper one laser cut for a turbo bike using a digital scan of the old one as a template. The copper cost more than the laser cutting.

 

I have made header gaskets out of sheet cooper also, i used the plasma cutter on worked fine

 

I made my 454 chevy exhaust gaskets out of .080 copper and they have been in there for years and thousands of miles are still good.

 

I made some years back for a SBC out of soft-as-dogshit copper sheet, .050 thick.

I stacked them up 4 high on a plate and cut them out on a mill. Really took very little time and I swiped the geometry off a blown-out composite gasket.

Bob

 

Thanks guys for the replys! - Tim

 

How about wrapping the inside of OEM gaskets with copper, just where the heat is? Might be easier the cutting new ones. Some of the 250 inline 6 gaskets come with steel wrapper inner holes, maybe look at them for ideas.

Joe

 

Need to make sure that there is enuf flex in the system if the engine is moving alot in the mounts need to make sure that the system can move with it.
You may want to install a flex joint somewhere between the flange and the first hanger.

 

I use copper roof flashing, it's thin stuff. but works well for exhaust gaskets.

I've made header collector flange gaskets from aluminum and it holds up well there.

Drill the bolt holes and corners of the big holes. Finish the big holes with a hand coping saw, fine tooth blade.

 

I make them for "non-standard" applications, as needed. What you are looking for is Dead Soft Copper. You can get small pieces from jewelry suppliers.

I have gotten stuff here: http://www.riogrande.com/Product/6-x-12-Copper-Sheet-18-Ga-Dead-Soft/132118

 

Copper can be Annealed by heating it red hot with a torch.

 

The roundy round boys around here swear by rtv silicone,i've seen the stuff run all year long on high rpm small block chevys,you'd think it would burn out.

 

Some header manufacturers specify it. Sanderson does. We keep with their instructions on their products. Yes, it does indeed work just fine. It seems like it should not, but it does. Crazy stuff.

I believe that the highest mileage, so far, on one we did, is about 35,000 miles. No leaks.

 

I only use silicone since the early 80s
only thing that last forever

 

ya might check your manifold to see if its warped