On a similar note, are any of you using slip joints with springs (or without) when you fabricate your exhaust systems? 

 

I also have a conversion concepts engine mount and the tubing on left side interferes with the manifold that came with my 13B and it will require me to run two distinct exhaust manifolds instead of the Racing Beat type that is a continuous manifold.  Are there any special rules of thumb / lessons learned when running two distinct manifolds like that?

 

Thanks for any insights / opinions.

 

Doug Lomheim

RV-9A, 13B

OK City, OK    

Gami?

 

Good stuff, those people make.

 

I am not familiar with the terms continuous vice distinct.

 

Stainless bends and tubing from Burns Stainless. 1 7/8" or 2" ID. Minimum of .062" wall. Primary lengths in multiples of 11", so, 11" or 22" or 33" 6" long collector to a 2 1/2" or 2 3/4" tail pipe to your muffler. Burns has some very nice stainless mufflers as well. Have a slip joint at the collector and in front of the muffler to allow freedom of movement for the engine. A pair of tabs on each tube with a stiff spring between pulling the tubes together is typical for aircraft and race cars. A safety wire hole in each tab and a loose fitting double wrapped wire run through the spring to the holes to retain the spring and the tubes in the event of a failure.

 

Use a length of shop vac hose or similar for a measuring device to get both primary tubes to the collector in exactly the same length, and entering at the same angle.

 

In stainless of at least .062" you can put heat wrap tape on the primaries with no danger and keep a lot of heat out of the cowl. In carbon steel, no tape at all, as the tubes will melt and fail. You can clamp the muffler tight but not the  tail pipe. This allows the engine to move about with no danger of failing a tube or muffler.

 

 

Lynn E. Hanover