Finn Lassen wrote:

Paul wrote:

The big question is, in addition to length, if you join the two exhausts do you get
a scavenging effect? The flow from one rotor's exhaust pulse helping to suck out the
exhaust from the other rotor. If so, how long do the headers need to be (before
joining at the Y) at say 6000 - 6500 RPM?

31 inches. If it gives you 15 more HP is is worth 5 pounds? That is three HP per
pound which is a way better ratio than your engine provides. That is the 10%
difference between a properly tuned pipe and a poorly tuned pipe based on 150 HP
to start. Probably with better BSFC in the bargain which will easily pay for itself
in short order at today's gas prices. PL

Ok, do we know for sure that it's 31" for the 13B ?

Finn

Nothing in this world is for sure Finn :-)
Best guess. Use a slip joint and see if you can tell the difference.
It worked well for Everett Hatch and Allan Tolle.

Paul Lamar
 
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