pipe clearance

[skydiverlv]

What is acceptable clearance for exhaust pipe to cowl and also exhaust pipe to area exit point below firewall? I have searched and get lots of advice on protecting these areas but no clearance minimums

[Mel]

Originally Posted by skydiverlv

What is acceptable clearance for exhaust pipe to cowl and also exhaust pipe to area exit point below firewall? I have searched and get lots of advice on protecting these areas but no clearance minimums

My personal minimum is about 3/4". Anything less than 1/2" will definitely hit. The engine moves around quite a bit, especially during start-up, shut-down, and high "G" maneuvers.

[bret]

what about thermal clearance minimum, at rpm-min airflow, run up? when does that cowl turn funny colors?

[Vlad]

I have less then 1/2" on mine due to engine sag and I can see a touch mark on the passenger side.

[airmel]

I found this article to be very helpful:

http://www.kitplanes.com/issues/31_5...p_20988-1.html

Information from Vetterman in this article -

"So, what kind of clearances does Vetterman recommend? "For unprotected fiberglass, I would recommend not less than 1? inches of clearance. For fiberglass with either foil or silver paint, you can reduce that to ? inch." The addition of an insulator like Fiberfrax will provide additional protection."

[6 Gun]

Vans foil does the trick.
Bob