RV-8 exhaust tail pipe brace improvements

[Ian Findlay]

Hi Listers,

See additional question below.

My RV8 has the early style exhaust braces and a 1.75" Vetterman System.

The engine is a 200HP AIB6 Angle Valve.

At 105 hours I have a cracked flange on #3 and a fine crack on #4 pipe.
I plead guilty to the crack in #4 as I stupidly fitted the big heat muff across a slip joint. However the #3 has cracked adjacent to the flange twice.

The system was installed with care with no residual loadings on the components. The flange nuts were retorqued after a few hours service.

I think I am able to find the now scarce later type exhaust hangers to fit the 1.75" system (the type with the support braces split and supported inside high quality hose with external hose clamps.)
These will come with instructions for proper assembly, I hope, because this is not quite as simple and intuitive as first imagined because I am told that the braces actually work in compression at times! ?

Does anyone out there have ongoing experience with these later type mounts please? Or any useful advice at all about earlier or later mounts for this engine, and prevention of exhaust cracking.

Cheers,

Ian Findlay
Albany Downunder.