X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail01.syd.optusnet.com.au ([211.29.132.182] verified) by logan.com (CommuniGate Pro SMTP 5.2.2) with ESMTPS id 2892182 for flyrotary@lancaironline.net; Sat, 03 May 2008 18:11:51 -0400 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.182; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-69-50.dsl.nsw.optusnet.com.au [220.236.69.50]) by mail01.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id m43MB2NV019846 for ; Sun, 4 May 2008 08:11:03 +1000 Message-ID: <003201c8ad6a$93ce2b40$6400a8c0@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Rotor Housings Date: Sun, 4 May 2008 08:11:02 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002F_01C8ADBE.64B47A40" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_002F_01C8ADBE.64B47A40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable The only number I have seen for lost HP was less than three with the = splitters. Exhaust design will be much easier with them. The tubes for your Pport should be thick walled and a light press fit, = in the inner wall in order to support the edges of the housing when the = stack is torqued up. Keeps the chrome from cracking. Fill in the water = void between inner and outer housing with an aluminum filled mechanical = epoxy. If there is no water, it can't leak. Devcon Plastic Aluminum if = you can find it. http://www.freemansupply.com/DevconEpoxyPlastic.htm The putty. Not the liquid.=20 Use a milling machine. Practice on a junk housing or two. Paul Yaw did = up a nice Pport and had the pictures on his web page. www.yawpower.com. = I'm on dial up until the 6th, so I didn't look through his stuff to see = if any of that was still there. Leave at least 1/2" of chrome on each = side to support the apex seal. I built one for a guy who ran it through two passes at an autocross = and never developed oil pressure.=20 Said it ran real good. It was in a Mini Cooper woody wagon. The engine = had set in his shop for two years before he ran it. (10 inch tires were = not enough) Keep runner (tube) ID about the same as the combined area of both = stock runners. High velocity is what you want. Bigger is not better = until you get closer to 10,000 RPM.=20 Cover all of the chrome you don't want ruined with three layers of = duct tape. Look for 200+ HP Lynn E. Hanover Lynn, I had be agonizing over runner diameter for a long time now and never = prescribed to PL's 2" runners for our use. I think I originally came to = my conclusions by doing a lot of surface area measurements on the = standard manifolds.=20 Anyhow there is a chap from the old Powersport who has a wealth of = experience on PL's site who has given some very useful info on their = developments, it would seem their final ( and current) inlet manifold = sizing is 1 11/16" ( 43mm) ID is almost exactly what my calculations = indicate for my single rotor development. Naturally I want the most out = of the single and am aiming for 125hp. The Powersport engine is claimed to produce 200hp at 6,000 rpm - = pretty good and not an outrageous claim. Extrapolating that to 7,500 one = would expect to see 250hp for the 2 rotor and therefore 125 seems doable = for the single. I have also opted for the RX8 high compression rotor and = cut it for 3mm apex seals - this should help me get there and that's at = 100 VE. If I get more VE with a tuned manifold , all the better. On tuned lengths, PL has tested an engine and got 240 hp ( I think) = with a 24" manifold, by working out the volume of the 2" OD tube and = dividing by the smaller tube I get a length of 30 "approx. The bottom line is, my approach is in line with your thinking and = agrees with Powersport, in regard to manifold tube diameter. I hoping = with a little more information I can tie down a more accurate = guesstimate on the length before I start putting it all together. I have put this up as 'grist for the mill' for other to consider in = line with PP sizing. George (down under) ------=_NextPart_000_002F_01C8ADBE.64B47A40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
The only number I have seen for lost HP was less than three with = the=20 splitters. Exhaust design will be much easier with them.
 
The tubes for your Pport should be thick walled and a light press = fit, in=20 the inner wall in order to support the edges of the housing when the = stack is=20 torqued up. Keeps the chrome from cracking. Fill in the water void = between=20 inner and outer housing with an aluminum filled mechanical epoxy. If = there is=20 no water, it can't leak. Devcon Plastic Aluminum if you can find it. = http://www.f= reemansupply.com/DevconEpoxyPlastic.htm
 
The putty. Not the liquid.
 
Use a milling machine. Practice on a junk housing or two. Paul = Yaw did up=20 a nice Pport and had the pictures on his web page. www.yawpower.com. I'm on dial up = until the=20 6th, so I didn't look through his stuff to see if any of that was = still=20 there. Leave at least 1/2" of chrome on each side to support the apex=20 seal.
 I built one for a guy who ran it through two passes at an = autocross=20 and never developed oil pressure.
Said it ran real good. It was in a Mini Cooper woody wagon. The = engine=20 had set in his shop for two years before he ran it. (10 inch = tires were=20 not enough)
 
Keep runner (tube) ID about the same as the combined area of both = stock=20 runners. High velocity is what you want. Bigger is not better until = you get=20 closer to 10,000 RPM. 
 
Cover all of the chrome you don't want ruined with three layers = of duct=20 tape.
 
Look for 200+ HP
 
Lynn E. Hanover
 
Lynn,
I had be agonizing over runner diameter for a long time now and = never=20 prescribed to PL's 2" runners for our use. I think I originally came = to my=20 conclusions by doing a lot of surface area measurements on the = standard=20 manifolds.
 
Anyhow there is a chap from the old Powersport who has a wealth = of=20 experience on PL's site who has given some very useful info on their=20 developments, it would seem their final ( and current) inlet manifold = sizing=20 is 1 11/16" ( 43mm) ID is almost exactly what my calculations indicate = for my=20 single rotor development. Naturally I want the most out of the single = and am=20 aiming for 125hp.
 
The Powersport engine is claimed to produce 200hp at 6,000 rpm - = pretty=20 good and not an outrageous claim. Extrapolating that to 7,500 one = would expect=20 to see 250hp for the 2 rotor and therefore 125 seems doable for the = single. I=20 have also opted for the RX8 high compression rotor and cut it for 3mm = apex=20 seals - this should help me get there and that's at 100 VE. If I get = more VE=20 with a tuned manifold , all the better.
 
On tuned lengths, PL has tested an engine and got 240 hp ( I = think) with=20 a 24" manifold, by working out the volume of the 2" OD tube and = dividing by=20 the smaller tube I get a length of  30 "approx.
 
The bottom line is, my approach is in line with your thinking and = agrees=20 with Powersport, in regard to manifold tube diameter. I hoping with a = little=20 more information I can tie down a more accurate guesstimate on the = length=20 before I start putting it all together.
 
I have put this up as 'grist for the mill' for other to consider = in line=20 with PP sizing.
George (down under)
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