REFLECTOR: Exhaust systems

Simon Aegerter reflector@tvbf.org
Fri, 11 Jul 2003 16:17:07 +0200


>After all, 3 does divide evenly into 6.

You are absolutely right, Dale.

A 6-cylinder engine fires 6 times during 2 full turns, that is 720 
degrees. 720/6 = 120. That means, the blasts are seperated by 120 
deg. That happens to be the spacing of the blades of a 3-blade prop. 
So. with a 6 cyl. engine and a three bladed prop you can have the 
blast in one of two places: onto the blades or between them, 
depending on how you mount the prop. Presto!

I have not flown a whole lot of hours since I turned my exhausts 
(3-in-1) backwards but I see no charring, just some soot.

Somebody asked about a 4-bladed prop. Same argument, different 
result: a 4-cyl fires 4 times in two turns - so 180 deg apart. unless 
you have 8 ways to mount your prop, you are making sure that at least 
two blades are hit every two turns.

Best
Simon
-- 
Simon Aegerter, Wollerau, Switzerland