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Hi Robert, I too used to have the Ford V6; loved the throaty
sound but not the weight. My conversion from the V6 to the 13B saved me 60lbs …
44 lbs for the FWF and 16 lbs of ballast in the tail!
Jeff
From: Rotary motors in
aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Rob
Sent: Thursday, February 05, 2009 1:59 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: 20B manifold
Thanks
Bill for your advise. I guess I will make my own, although it seems the Reneses
manifold is quit well constructed to reduce noise as well as stand up to the
heat in conjunction with a muffler, based on what I have read on this list so
far.. What I'm most concerned about is the noise. I currently fly a BD-4
with a Ford V-6 and I'm constantly trying to get the noise to some reasonable
level. Would adapting the Reneses be worth the trouble, in your opinion?
Or how about adapting two 13-B manifolds? Any thoughts on this would be
appreciated.
Robert
Bollinger
MR 722, 1000 N,4th ST
Fairfield IA 52557
(641)919-3213
rob@mum.edu
-----
Original Message -----
Sent: Thursday, February
05, 2009 11:00 AM
Subject: [FlyRotary] Re: 20B
manifold
Robert,
The manifold could probably be lightened for non-turbo applications. The
problem is that if you remove material in the wrong place the cast iron is
likely to crack. Even if you want a non-tuned log manifold you are going to be
way ahead by making it from SS tubing and plate. The only reason for the cast
manifolds at all is the ability to make them cheaply in production.
Bill Jepson
-----Original Message-----
From: Rob <rob@mum.edu>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, 5 Feb 2009 8:16 am
Subject: [FlyRotary] Re: 20B manifold
Do
you think the 20B manifold could be lightened or would it be a waste of time to
even attempt it.
Robert Bollinger
MR722 MUM
Fairfield IA 52557
(641)472-7000 ex2068
(641)919-3213 cell
rob@mum.edu
-----
Original Message -----
Sent: Wednesday, February
04, 2009 12:46 PM
Subject: [FlyRotary] Re: 20B
manifold
Rob,
I have a 20B and the manifold without the turbos is a very heavy chunk of cast
iron. I don't think it would be in danger of melting, but is just too heavy. I
do NOT believe the Renesis Exhaust manifold would be made to fit practically.
The Renesis has side ports with a rectangular profile. The 20B is a 13B with an
extra rotor and one of the spacings is longer due to the intermediate housing.
The best method is going to be a built up manifold, aand several are available
over the counter. Usually expensive, but much less hassle. Racing Beat made one
for using a single turbo for racing in the past. I don't know if it is still
available.
Bill Jepson
-----Original Message-----
From: Mark Steitle <msteitle@gmail.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, 4 Feb 2009 9:34 am
Subject: [FlyRotary] Re: 20B manifold
The Renesis manifold has an inner shell, an outer shell, and
a heat shield on top of that. I'm not positive, but the inner
shell could possibly be made of inconel. The outer shell
appears to be stainless (probably 321).
Since the Renesis has three exhaust ports, I have often
wondered if it could be modified to work on a 3-rotor. Keep in mind that
the port spacing on the Renesis is the same while the 20B unequally
spaced. That's due to the one larger side housing that contains the
3rd main bearing. So, if the ports are big enough, and the
bolt pattern matches, you would still have to add an extension between two
of the ports to make it line up. If that is all it requires to make
it fit, it could be worth a try.
On Wed, Feb 4, 2009 at 11:12 AM, Rob <rob@mum.edu> wrote:
I
would be interested to know the weight. I didn't realize that a cast exhaust
manifold made for a 20B could actually melt. It sounds like the Renesis
manifold would be better.. Is the Renesis manifold stainless steel or
what?
Robert Bollinger
MR722 MUM
Fairfield IA 52557
(641)472-7000 ex2068
(641)919-3213 cell
rob@mum.edu
-----
Original Message -----
Sent: Wednesday, February
04, 2009 8:10 AM
Subject: [FlyRotary] Re: 20B
manifold
I have one that came with my 20B. I don't want to
sound negative, but I don't think it is realistic to use on an a/c.
First, it is incredibly heavy because it is designed to incorporate the twin turbos.
And it is made of cast iron, so it would probably melt at prolonged WOT
operation. And the passages are very restrictive to
exhaust flow. I could weigh mine and send some pictures if you
wish. Sorry, but I don't want to get rid of it because I have plans for a
3-rotor auto installation where it would be useable. Maybe you could
modify a Renesis manifold to fit. It would require some welding, but it
is probably more likely to work than the original 20B manifold.
The cheapest manifold would be to use 304SS handrail
material. I built my first manifold using that material and after 100
hours it looks like it would last for a very long time. Ed Anderson has
been using this material on his a/c for a long time. My exhause flange
material was 1/2" mild carbon steel and it was holding up fine as it
doen'st see the high heat that the pipes do. The problem was with the
mufflers. They take a real beating. Try to space the muffler as far
away from the engine as possible.
On Wed, Feb 4, 2009 at 7:43 AM, Rob <rob@mum.edu> wrote:
Thanks
for your replys on this subject. I realize the manifold would be too heavy but
I was hoping I could widdle it down some how. Greg, I would be interested in
your suggestion for doing that. I'm putting this 20B in a BD-4.
Robert Bollinger
MR722 MUM
Fairfield IA 52557
(641)472-7000 ex2068
(641)919-3213 cell
rob@mum.edu
-----
Original Message -----
Sent: Tuesday, February
03, 2009 11:10 PM
Subject: [FlyRotary] Re: 20B
manifold
Al, you don't want
the stock exhaust. Get one built. If you want to know one way it's
done, let me know.
-----
Original Message -----
Sent: Tuesday, February
03, 2009 8:25 PM
Subject: [FlyRotary] Re: 20B
manifold
Does
anyone on this list have a 20B exhaust manifold that came with their
engine that I could buy?
No; but I do know the thing is massively heavy. I looked at
one when I got my engine, and decided quickly it was not very interesting for
an aircraft. Maybe if radically modified . . . Just my opinion.
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