Thanks, Dennis,
It sounds like you still have a little unused throttle
travel even with the new intake.
Can you provide design measurements for your new
intake? I ask only if you have no plans to make and sell it.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Dennis Haverlah
Sent: Friday, February 12, 2010
2:20 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: rpm vs
Power was : Throttle limits was Re: N.A. Renesis to turbo
I used the same 65 mm Mustang throttle body on both my
original and new intakes. If I remember correctly, I believe I had
a longer unused throttle travel with the original intake but I never
measured it. I don't know the static rpm increase with the new intake -
probably have that in my notes some where but my max. rpm at high altitude
(8,000 - 10,000) increased 400-500 rpm. I estimated I went from 165 -170
HP with the old intake to about 185 HP with the new intake. This in in
line with Ed Anderson's recent note that Mazda got about a 16% power increase
at 6000 rpm with the DIE effect. I felt much improved acceleration the
first time I took off with the new intake.
the new intake is based on dynamic intake
effect (DIE) where the closing of an intake valve caused the
moving intake air to bounce off the valve creating a pressure wave. The
wave travels at the speed of sound to the other intake valve and arrives there
just before that valve closes. This increases the amount of air and fuel
that enters the combustion chamber. (As we know the rotary has no valves
but uses the sides of the rotor for opening and closing the intakes.) I
designed my intake to give max. performance at 6300 rpm.
If I had cut down my prop to 74" it would give me more clearance for the
prop on my RV-7A and increase my top end rpm. Max rpm is about 6400
rpm with the new intake and the 76" prop. I'm really not needing
higher RPM now.
Dennis Haverlah
Bill Bradburry wrote:
Dennis,
Did your static rpm increase with the new
manifold? How much? Did you before and do you now have any unused
throttle travel like Mike describes? Are you using the same
throttle body on the new manifold? What is the MM opening of the Mustang
body?
My manifold is very similar to your old one. My
tubes are cut just above the injector bosses, which makes them a little (maybe
an inch) shorter than your old ones. I have a 76 X 88 Performance prop
which I am considering having cut down to 74” like Tracy and Ed when I
send it in for final finish. I am using an aftermarket throttle body that
is 75MM in throat diameter. This is the same size as the stock Renesis
throttle body which is why I picked it. I had intended to use the Renesis
body, but didn’t wait for Tracy
to get the fly by wire done. I am not flying, but my static is 52-5300
rpm and I have a lot of throttle left at that rpm. The last probably ¼ of
the travel is not used.
Bill B