X-Virus-Scanned: clean according to Sophos on Logan.com From: "Bill Bradburry" Received: from vms173021pub.verizon.net ([206.46.173.21] verified) by logan.com (CommuniGate Pro SMTP 6.0.9e) with ESMTP id 6996248 for flyrotary@lancaironline.net; Thu, 24 Jul 2014 00:02:39 -0400 Received-SPF: pass receiver=logan.com; client-ip=206.46.173.21; envelope-from=bbradburry@verizon.net Received: from Desktop ([unknown] [173.57.170.65]) by vms173021.mailsrvcs.net (Sun Java(tm) System Messaging Server 7u2-7.02 32bit (built Apr 16 2009)) with ESMTPA id <0N9700M0E7786B00@vms173021.mailsrvcs.net> for flyrotary@lancaironline.net; Wed, 23 Jul 2014 23:02:01 -0500 (CDT) To: "'Rotary motors in aircraft'" References: In-reply-to: Subject: RE: [FlyRotary] Re: Rv7 renises p port Date: Wed, 23 Jul 2014 23:01:57 -0500 Message-id: <18799567A05A4626AA767FE2849C3678@Desktop> MIME-version: 1.0 Content-type: multipart/alternative; boundary="----=_NextPart_000_0018_01CFA6CA.1D9396D0" X-Mailer: Microsoft Office Outlook 11 Thread-index: Ac+m2Jks2QrBF8DHTD6W8DGdGjOW1QAGnNWw X-MIMEOLE: Produced By Microsoft MimeOLE V6.0.6002.18463 This is a multi-part message in MIME format. ------=_NextPart_000_0018_01CFA6CA.1D9396D0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit James, I don't know if you are using Tracy's EC-2 or 3, but it has a rev limiter somewhere around 7500 rpm. I don't know what would happen if you invoke this limiter but it might be scary. :>) I try to limit my Renesis to about 7200 rpm in order to stay away from the limiter. Do you have any pictures of the P Port for the Renesis? Did you substitute any parts to do this? Bill _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] Sent: Wednesday, July 23, 2014 7:45 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Rv7 renises p port I don't know jack about slippage, but I think it is the percentage difference between actual distance traveled and theoretical distance traveled if your propeller corkscrewed through the air with no thrust. B I found a prop slip calculator online and for 86 inch pitch, 2.85 gear ratio, 7000 rpm, 180 mph, I get 10% slip. B Granted the calculator was for boat propellers, but I don't think it matters as long as the units are correct. B There has to be some slip because there would be no thrust otherwise. B So what is considered a reasonable or good amount of slip? B Using Bill's numbers 86 inch pitch, 2.85 gear ratio, 7000 rpm, 200 mph, I get 0% slip. B That can't be right! On Fri, Jul 4, 2014 at 7:19 AM, Bill Bradburry wrote: Christian, It seems that you have a lot of prop slippage at cruise. B I think that at that prop rpm you should be getting 200mph if you had no slippage. Bill -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] Sent: Thursday, July 03, 2014 4:01 PM To: Rotary motors in aircraft Subject: [FlyRotary] Rv7 renises p port Well hi all Just thought I'd throw out there the mods I,ve done to the renises in an rv7'. Well the p ported engine is now back in the plane and running well, over the standard short manifold that was originally in the plane I have gained around 400 static rpm, same prop and gearbox combo, 2.85 ratio, this equates to allot more hp at takeoff, just shy of 2300 prop rpm, I'm running a prince p tip prop at 68" x 86" pitch, At 8000 ft it is turning 7000 at 180 mph tas which is an improvement of 25 mph on previous tests, . So next plan is bigger prop and less pitch to let it rev to 7500 in strait and level. Cheers Christian Rv7 renises Aus Sent from my iPad -- Homepage: B http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html -- Homepage: B http://www.flyrotary.com/ Archive and UnSub: B http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0018_01CFA6CA.1D9396D0 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

James,

 

I don’t know if you are using = Tracy’s = EC-2 or 3, but it has a rev limiter somewhere around 7500 rpm.  I don’t = know what would happen if you invoke this limiter but it might be = scary.  :>)  I try to limit my Renesis to about 7200 rpm in order to = stay away from the limiter.

 

Do you have any pictures of the P = Port for the Renesis?  Did you substitute any parts to do = this?

 

Bill

 

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
Sent: Wednesday, July 23, = 2014 7:45 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = Rv7 renises p port

 

I don't know jack about slippage, but I think it is the = percentage difference between actual distance traveled and theoretical distance = traveled if your propeller corkscrewed through the air with no thrust. B I found = a prop slip calculator online and for 86 inch pitch, 2.85 gear ratio, 7000 rpm, = 180 mph, I get 10% slip. B Granted the calculator was for boat propellers, = but I don't think it matters as long as the units are correct. B There has to = be some slip because there would be no thrust otherwise. B So what is considered = a reasonable or good amount of slip? B Using Bill's numbers 86 inch pitch, = 2.85 gear ratio, 7000 rpm, 200 mph, I get 0% slip. B That can't be = right!

 

On Fri, Jul 4, 2014 at 7:19 AM, Bill Bradburry <flyrotary@lancaironline.net> wrote:

Christian,

It seems that you have a lot of prop slippage at cruise. B I think that = at
that prop rpm you should be getting 200mph if you had no slippage.

Bill


-----Original Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net]
Sent: Thursday, July 03, 2014 4:01 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Rv7 renises p port

Well hi all
Just thought I'd throw out there the mods I,ve done to the renises in = an
rv7'.
Well the p ported engine is now back in the plane and running well, over = the
standard short manifold that was originally in the plane I have = gained
around 400 static rpm, same prop and gearbox combo, 2.85 ratio, this = equates
to allot more hp at takeoff, just shy of 2300 prop rpm, I'm running a = prince
p tip prop at 68" x 86" pitch,
At 8000 ft it is turning 7000 at 180 mph tas which is an improvement of = 25
mph on previous tests, . So next plan is bigger prop and less pitch to = let
it rev to 7500 in strait and level.

Cheers
Christian
Rv7 renises Aus


Sent from my iPad
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