Subject: Exhaust tuning
From: Paul
Date: 10/23/2000, 10:45 PM


Finn Lasses wrote:

Thanks for the chart, Paul.

Now, what about a two-rotor system. Is there any power
advantage/disadvantage of running separate pipes/mufflers vs. joining
them very near the ports?

I'd hate to add more weight than absolutely needed. Least weight would
be making a Y close to the ports and running a 2" pipe from there.

BTW, Ed, I don't see any flex points in your system?

Finn

I would run separate pipes and separate mufflers like Ed did. I think
you could use 0.035 316 SS. By the time you get back to the mufflers
the exhaust should have cooled off a bit and they should last longer
than 1000 hours such as Tracy got out of his. 16 pounds seems a lot
for mufflers. I like your idea of opening the front of the concentric pipes.
That should cool the guts without increaseing the noise too much as
the slipstream should flow a lot of cooling air through there. This is a picture
of the early Power Sport engine with the 30 inch tuned pipes.

Paul Lamar

Opps. That should be 0.035 316 SS for the mufflers and not the pipes.
I think the pipes should be something thicker like .065 316 SS near the engine
and .049 316 SS a foot or two away from the engine.

Paul Lamar
 
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