Exhaust Wrap

[SonexN76ET]

I was wondering what other builder's experience has been with wrapping their exhaust? Did you see any tangible performance improvement or benefit? Did you have to adjust the mixture on the Aerovee after wrapping?

I just wrapped mine and it seems a little smoother, but my engine is balking at full throttle on my run ups. I am either going to have to lean my mixture or retard my throttle slightly. Frustrating...

Jake

[wlarson861]

The biggest thing I noticed was the EGT ran higher but the CHT dropped and along with removing the gascolator I eliminated the burps.

[gammaxy]

I would expect that if the exhaust wrap was having an effect, it would be causing the air in the cowl to be cooler and denser than before and require a slightly richer mixture.

After a winter of flying in 25-40 deg. F temperatures, I flew the other day when it was 70+ degrees and had to lean the mixture for the engine to run smoothly while taxiing to the runway (during the winter, I could taxi full rich fine, but I lean it out just in case it makes a difference at the spark plugs). I did a higher-than-usual power run-up to find a good setting for the mixture on takeoff. Afterwards, I did a quarter turn adjustment on the Aeroinjector and flights since then have been great. I knew I was a little too rich when it was cold outside, so I'm hoping this adjustment moves me closer to the "sweet spot" and I won't need to adjust it if it gets cold again.

[SonexN76ET]

I had to switch my needle from a 2.5 to a 2.0 in order to get the engine to run within specifications after wrapping the exhaust. I still have some slight mixture adjustments to make before I put out any endorsements of wrapping the exhaust. So far I have seen no performance benefit that justifies the weight and shortened exhaust system life. It was also a real head scratcher to figure out how to get it tuned up again after installing the wrap.

Jake