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You must have had streight pipes out the side of
the cowl. Mine go under the cabin. My BD-4 with the 20B should be about the same
weight or less as the Ford V-6.
Robert
Robert Bollinger MR 722, 1000 N,4th ST Fairfield IA
52557 (641)919-3213 rob@mum.edu
----- Original Message -----
Sent: Thursday, February 05, 2009 1:14
PM
Subject: [FlyRotary] Re: Ford V6 ... was
20B manifold
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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