Not Al, but my 0.02 is that if you have
good mixture velocity in your intake then what you are using to get it is
rather moot.
In Al’s case, he is using a three
throat TWM TB and has a 3 rotor 20 B, so that clearly makes for a good match
up. My two rotor was clearly “over throated” resulting in low
air velocity and the only way to get good runner velocity was to have the
engine over 8000 rpm – but, of course, prop load and no gear box to shift
load precluded reaching that magic rpm regime – besides my prop tips
would have been supersonic if I had. If I had used this TWM set up with 40
-45mm dia holes rather than the two 50 mm dia holes – my results would
undoubtedly have been better.
You really have to pay attention to the
details – as that is where the devil is (so I’ve been told).
Trying to put on a 2 rotor a three rotors induction system or vice versa is
unlikely to give good results in either case. Matching your induction system
to your engine size and rpm regime of operation is the core of getting good
results.
I agree with, Al. Its likely that using
half of the four ports shown in the photo of the TWM TB would be a good
combination. However, depending on how much you like to experiment and
fabricate, you could try it with the 4 and if that failed to give you good
results, you could down-size to two.
Keep us posted, we all like to see experimentation.
Ed
Ed Anderson
Rv-6A N494BW Rotary Powered
Matthews, NC
eanderson@carolina.rr.com
http://www.andersonee.com
http://www.dmack.net/mazda/index.html
http://www.flyrotary.com/
http://members.cox.net/rogersda/rotary/configs.htm#N494BW
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bryan Winberry
Sent: Saturday, February 07, 2009
4:09 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: renesis
intake possibility
How is your set up different than the one Ed A. had
that didn't work too well? It was also
one throttle split into two runners.
Bryan
--- On Sat, 2/7/09, Al Gietzen <ALVentures@cox.net>
wrote:
From: Al Gietzen
<ALVentures@cox.net>
Subject: [FlyRotary] Re: renesis intake possibility
To: "Rotary motors in aircraft"
<flyrotary@lancaironline.net>
Date: Saturday, February 7, 2009, 3:04 PM
I use a 3-barrel TWM TB on my 20B with 44mm
barrels. One barrel (which divides into the 2 runners) for each rotor.
It seem to work quite well. As Ed mentioned, and supported by Paul Yaw¢s work, high velocity in the barrel is a good thing.
Maybe you could cut the thing in half and use 2 barrels? I use the injector
port in the TB for MSD (Rochester) injectors, and use the stock primary in the housings.
Al
-----Original Message-----
From: Rotary
motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Bryan Winberry
Sent: Saturday, February 07,
2009 5:57 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] renesis
intake possibility
I
have a chance to purchase a TWM throttle body(see attch pic) at a very
low price. I have a couple questions for the group.
The
inlets are 42mm (appx 1.65 in.). Is this too big to the point
that they would be incompatible with the injectors? I plan on using
1-1/8 and1-1/4 in runners.
Also,
the bosses are sized for Bosch, Rochestor, or Lucas injectors.
Does this necessarily eliminate my using the stock Renesis injectors?
This
setup also would allow the use of a lightweight airbox thus
simplifying the intake system from a manufacturing standpoint.
RV7,
Renesis,RD-1C,EC3,EM3 (in the pipeline I hear)
|
|