Received-SPF: none
 receiver=logan.com; client-ip=204.127.217.105; envelope-from=bbradburry@bellsouth.net
From: "Bill Bradburry" <bbradburry@bellsouth.net>
To: "'Rotary motors in aircraft'" <flyrotary@lancaironline.net>
References: <list-5612264@logan.com>
In-Reply-To: <list-5612264@logan.com>
Subject: RE: [FlyRotary] Re: MAP drop
Date: Thu, 21 Jun 2012 14:38:02 -0400
Message-ID: <B855BDCE92434E6B85192ABE33086B3E@Desktop>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit
Thread-Index: Ac1Pz8VDSYpI2PqzSneOk0BBrtTZswADGJnQ

That is an interesting concept!  How would you duct the incoming air to the
center of the fan?  You don't have much room in there.  :>)

But if it is not working, you should notice when you remove it.  I saw where
the fan pulls 16 HP at 6K rpm.  I think it puts out about 2 inches at that
speed, so the net should be some improvement provided it works as planned.

Bill B

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On
Behalf Of Ernest Christley
Sent: Thursday, June 21, 2012 1:00 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: MAP drop

Bill Bradburry wrote:
> I don't think I get much pressure drop across the filter, but I don't know
> what the rest of the intake does.  I would like to get a pressure reading
at
> the entrance to the rotor to see what the drop is for the entire intake
> manifold and filter.
> 
> It seems like an AFR of 16 is lean for turbocharging during a takeoff
run??
> 

Not a turbo.  A blower.  A centrifugal blower from a '67 Corvair cooling fan
situated between the engine and PSRU.  I
wasn't expecting to get a lot of MAP boost, but it looks like I'm not
getting anything.  The only way to really tell
would be to remove the fan and do a couple runs without it in the system.

  The 16 AFR is at idle, and basically everything below WOT where I'm not
trying to make significant power.  After WOT,
the throttle turns into a mixture control and will currently push it all the
way down to 11.5.  But I'm seeing RPM drop
off below 12, so I'm going to set that as my bottom limit.

> I don't guess I understand why you want your manifold pressure to read in
> "percentage of ambient"??  Why not just inches??
> 

Don't have a choice in the matter.  That is what the MegaSquirt
computer/firmware/software stack gives me, so I deal
with it.  Though, for programming purposes, I can see how it sure would make
the computations simpler.

--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:
http://mail.lancaironline.net:81/lists/flyrotary/List.html