Yes I know :(

Can you shorten it to 8.5 inches? That would be optimum for
the manifold to actually work as a dynamic chamber. At 17 inches
and 6000 RPM it is working as four tuned pipes (two at one length
and two at another length) feeding off two piss poor plenums :)
At 17 inches it is working as an actual dynamic chamber only at 3000 RPM.

As far as the slightly different lengths are concerned an electronic
analogy would be two series resonant circuits tuned
at slightly different frequencies in parallel. The impedance would
be lower if they were both tuned at the same frequencies
and the bandwidth narrower.

Hopefully Jerry Hey will have a p-port engine running soon
and it is easy to vary the runner length so we may have some dyno

data on this soon. The dyno is close to being done. All I need now
are some engines to run on it.

Okay, if one was to "tune" for 6K rpm using 8.5 inch runner lengths, what
happens at a lower cruise rpm of say 4500 ? Will the power be substantially
reduced and / or will fuel consumption be adversely affected?
Wendell

The fuel economy will suffer but that is an extremely low RPM for
an aircraft rotary. Stay tuned I am addressing that issue.

Paul Lamar

********************************************************************************

Paul;.........Being rather ignorant in all this Intake Tuning, Dynamic Chamber,
and Plenum Chamber etc. stuff, I find myself bouncing between GETTING IT,
DUMBFOUNDED BY IT and NOT GETTING IT AT ALL :(
So I'm counting on the likes of YOU in the list on setting specific guidelines
of all this so that the likes of ME on the list don't kill themselves :)

That is..........Unless a miracle should happen in the interim, and I finally
GET IT ;-)

                                                             Butch

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