Header to sidepipe flange Gasket material?
 

Hi
I will getting my headers and sidepipes back from the coater today or tomorrow.
Was wondering what do I use for material for the big square header to sidepipe flange. This collector face is flat and has the four holes in it. Obviously we have to cut something out for it.
Its not the slip joint style some have.

Where I work we have access to sheets of high heat stuff made by Garlock. I was also told of using sheets of copper?

What are you guys doing for this one

Tim

Mr gasket brand sheet stock. Hold it up to the flange and "tap out" the holes with a ball peen hammer.

Thanks for the reply and the info I will look into that

Tim

I use UltraCopper RTV-like gasket goo without any gasket. I'm pretty sure DV recommended it and it seems to work great.

On our 4n24 style flanged, we've had excellent luck with 1/8" aluminum w/ULTRACopper on eachside. Never any leaks or bolt loosening, that's what you're looking for.

Grumpy's Garage

Red high-temp RTV...no gasket.

Rich

I'm with grumpy.
I've used "dead soft" aluminum on several cars with never a leaker. And they're reusable if necessary with no messy cleanup.

Bob what do you mean by dead soft aluminum? Is it different than the 1/8 sheet

Guys its looks like the ultracopper RTV sealant is a popular choice as well

Could be interesting cutting the aluminum 4 holes in each flange.

Reminds me of when I cut my dash for my gages

Tim

Hey Tim,

Aluminum is alloyed for various purposes, so thickness isn't the criterion. My applications have all been the standard 3" collector end. The "gaskets" I refer to are available from Summit. There may be some guys on the site here who are into metalurgy and would know better how to explain it, or know the i.d. number for this particular alloy, but you might try a metal supply house in your area and see if the term "dead soft" is some form of standard terminology, or industry slang. From observation it is a soft alloy of aluminum that is easily compressed (relative terms) which must be what contributes to the sealing. One thing I have noticed is that it will make a "clicking" sound as it thermal cycles that I didn't notice before I installed them. I don't find it annoying, but others might.

Hello Bob...thanks for the reply. After some looking, I see that they use deadsoft aluminum on a lot of collector and header gaskets. Also copper in a deadsoft form is used. My builder had mentioned along time ago something about sheet copper that had been softened.

Anyway heres a neat link to sealant properties. They have goofed on the RTV grey tem at 700 deg F its actually 625

http://alphasourceintl.com/seal/sealant_properties.htm

But neat to compare. The temp limit on Ultracopper at 700 deg F

Doesn't that seem low still for exhaust temps? I would expect the collector flange to be pretty warm

Tim

Like Petek said. DV recommended copper RTV. Just put a 1/4" bead and bolt together. NEVER leaks. I've had my pipes apart several times for various reasons and the seal always looks perfect.

Jim Downard

Hi Jim I am thinking about the RTV bead if the metal solution is "undoable". Sounds easy as it is a gasket maker.

On deadsoft etc heres a bit of info

Dead Soft Annealing
Heating metal to above the critical range and appropriately cooling to develop the greatest possible commercial softness or ductility.

Dead Soft Steel
Steel, normally made in the basic open-hearth furnace or by the basic oxygen process with carbon less than 0.10% and manganese in the 0.20-0.50% range, completely annealed.

Dead Soft Temper
Condition of maximum softness commercially attainable in wire, strip, or sheet metal in the annealed state.

Now as my builder had said he mentioned sheet copper...so

" Copper
This metal and its alloys have many desirable properties. Among the commercial metals, it is one of the most popular. Copper is ductile, malleable, hard, tough, strong, wear resistant, machinable, weldable, and corrosion resistant. It also has high-tensile strength, fatigue strength, and thermal and electrical conductivity. Copper is one of the easier metals to work with but be careful because it easily becomes work-hardened; however, this condition can be remedied by heating it to a cherry red and then letting it cool. This process, called annealing, restores it to a softened condition. Annealing and softening are the only heat-treating procedures that apply to copper. Seams in copper are joined by riveting, silver brazing, bronze brazing, soft soldering, gas welding, or electrical arc welding. Copper is frequently used to give a protective coating to sheets and rods and to make ball floats, containers, and soldering coppers."


Sounds easy enough. Heck if the flange surface is less than perfect why not do both? Use a metal gasket and supplement it with RTV?

Jim can you apply it, bolt her up and drive away, or should you let it cure??

Tim

Have had major problems with hi-temp RTV and ultra-copper rtv. Recently picked up some black hi-temp gasket "paper" from a local auto store, and it works like a charm. Looks like it will hold out in the long-term test, but only time will tell.

Cheers,
-Neil.

I believe the dead soft aluminum you are talking about has the spec number 1100 which as I recall is pure non alloyed alum.

I have tried using aluminum spacers to get the sidepipes further away from the body on some cars with limited success. The aluminum "goes away" and eventually blows a hole out the side. I have also tried using hi temp RTV as exhaust gasket material with mixed success. It starts out OK but starts leaking not too long later. I have had the best luck using Mr.Gasket's sheet stock of header gasket material and tapping out my own gaskets with a little ball peen hammer.

Sounds like the best bet may be sheet stock gasket material

I have a gasket cutter kit and its fairly easy to cut out the 4 perfect circles, I had tried the same thing with my carb gaskets... practically the same beast except the carb has 1 3/4 butterflies and the exhaust has 2 " primaries
8 bolt holes instead of 4.

LOL

Thanks again

Tim

annealing
 

Copper has been described already to anneal or soften. The key is in the cooling process. Copper is cooled slowly gradually reducing the heat. Aluminium is heated to a temp close to melting, be careful because it doesn't get red hot it goes glub. A good indicator is bar soap rubbed on it and when it burns or turns black it is cooked. It can be easily heated with a plumbers torch or a mapp gas torch. The big difference is in the cooling you dunk aluminium in water to cool it rapidly. Both make good gaskets and have high thermal conductivity to sink the heat away, if you have a real nice metallic match on both surfaces I would consider just the HiTemp RTV. You'll make it work they don't have much back pressure to worry about!
Cheers Nick

Wow,
You guys do like to make work for yourselfs! :) The aluminum sounds like a heck of an idea, but expensive and extra work.

Mrfixit, you mean you've actually blown out permatex's rtv hi-temp sealer. Wow.

We use Ulta Gold RTV Hi-temp. on all our exhausts flanges, including the V-10's. On a good run our temps will hit 1125 on left and right tubes, even at these temps we have never blown out a seal.

As far as taking them apart, I haven't found a problem. Just grab an available edge and peal like a rubber band. If there is any residue left, when I re-do them I just "drag" a razor blade over the surface and go again.

That's my story and I'm sticking to it!

DV-- We need your support and attendance! Have you bought your raffle tickets?

I got my hands on some gasket material that is called "graphite"
Its just like what my header gaskets are made of....dark gray and slippery feeling.

The only bugger is that it has a steel mesh woven into it that may make cutting the circles a chore. I guess I could use a gasket punch on the circles. Supposed to be good for 2700 Deg

Tim

Ultra-copper RTV. 15000 miles, no leaks :D