X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-mb01.mx.aol.com ([64.12.207.164] verified) by logan.com (CommuniGate Pro SMTP 5.3.8) with ESMTP id 4365733 for flyrotary@lancaironline.net; Mon, 21 Jun 2010 18:41:52 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.207.164; envelope-from=WRJJRS@aol.com Received: from imo-ma04.mx.aol.com (imo-ma04.mx.aol.com [64.12.78.139]) by imr-mb01.mx.aol.com (8.14.1/8.14.1) with ESMTP id o5LMf0hX020070 for ; Mon, 21 Jun 2010 18:41:00 -0400 Received: from WRJJRS@aol.com by imo-ma04.mx.aol.com (mail_out_v42.9.) id q.e75.d4ee1f (37688) for ; Mon, 21 Jun 2010 18:40:56 -0400 (EDT) Received: from smtprly-dc02.mx.aol.com (smtprly-dc02.mx.aol.com [205.188.170.2]) by cia-mb08.mx.aol.com (v129.4) with ESMTP id MAILCIAMB084-d3874c1fea74259; Mon, 21 Jun 2010 18:40:56 -0400 Received: from webmail-m081 (webmail-m081.sim.aol.com [64.12.108.97]) by smtprly-dc02.mx.aol.com (v129.4) with ESMTP id MAILSMTPRLYDC027-d3874c1fea74259; Mon, 21 Jun 2010 18:40:52 -0400 References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: 13B rotary engines Date: Mon, 21 Jun 2010 18:40:52 -0400 X-AOL-IP: 65.113.35.181 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: wrjjrs@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CCDFA9F01A23F2_291C_D74A_webmail-m081.sysops.aol.com" X-Mailer: AOL Webmail 31888-STANDARD Received: from 65.113.35.181 by webmail-m081.sysops.aol.com (64.12.108.97) with HTTP (WebMailUI); Mon, 21 Jun 2010 18:40:52 -0400 Message-Id: <8CCDFA9F0109E72-291C-6AAE@webmail-m081.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: WRJJRS@aol.com ----------MB_8CCDFA9F01A23F2_291C_D74A_webmail-m081.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Bryan, As a reference the original Powersport 13B P-port is rated at 210 HP norma= lly aspirated. The fuel flows are very similar to any other engine produci= ng that level of power. Steve tells me that they were seeing FF very compa= rable to an angle valve IO-360 producing identical power. This engine was= dynoed with butterfly valves in the housing. These p-ports were 1-5/8' di= ameter optimized for 6000 RPM. The engine would rev higher but you were al= ready at peak power anyway. Larger ports will make more power at higher RP= M. Tuning will become more critical with the larger ports. A personal anec= dote here. I built a high reving motorcycle engine in 1978 with all the "b= est" parts at the time. The engine was unreal at high revs, but if you tra= nsitioned to anything below 4000 RPM by shutting the throttle off and quic= kly opening it again the engine would "catch" or hit an RPM plateau and wo= uld rev no higher. In fact the engine would die if not returned to idle!= This horrible malfunction was TUNED OUT later, and the solution was surpr= isingly simple, however difficult to find. The key here is that many peopl= e underestimate the job of installing and tuning p-ports. There are two as= pects, first the initial install being sure there are no leaks . Then seco= nd, and most overlooked is that the system must tolerate the heat cycles= of a high power engine without DEVELOPING NEW LEAKS for a long time. Powe= rsport used an insert with o-rings sealing the port. O-rings or other elas= tomers work much better than epoxy on long-term sealing because there are= different expansion rates between the port and the epoxy. On a car you ca= n usually get away with epoxy for a while. An aircraft is a different anim= al. The aircraft engine needs to tolerate 80-100% power for long periods= and then long cold-soaks on the ground. The rotary is mechanically tough= enough but you need to design your subsystems like a race car that will= see a 500 mile long straight-away! When Paul Lamar ran one of the newsle= tter guys P-port Renesis at MazdaTrix, They got great numbers, but only af= ter changing to an intake that MazdaTrix had spent lots of time tuning. P-= ports will run great, and even idle well if not too oversized, but don't= expect the tuning to be real easy. Remember you are designing a new intak= e, exhaust, and the equivilent of a new cam timing all at once. The rotary= is very much like a two-cycle in that respect. The results can be very wo= rth while if you understand the difficulty involved. Bill Jepson -----Original Message----- From: George Lendich To: Rotary motors in aircraft Sent: Mon, Jun 21, 2010 2:36 pm Subject: [FlyRotary] Re: 13B rotary engines Bryan, Not all P-ports are equal. More power =3D more fuel. Talk to Bill Jepson ( on here) about availability of new P-ports. George ( down under). All this talk of additional power coupled with an easier intake design has= me thinking I should probably go this direction with my Renesis. It=E2= =80=99s still on the stand after rebuild. I haven=E2=80=99t constructed the manifold yet anyway. =20 I assume fuel flow will be higher than normal? =20 Is slide throttle best option? =20 Need to search archives I guess. =20 Good info Lynn, Thanks =20 Bryan =20 =20 =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Be= half Of Lynn Hanover Sent: Monday, June 21, 2010 12:15 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: 13B rotary engines =20 In a message dated 6/21/2010 11:03:01 A.M. Eastern Standard Time, rv-4mike= @cox.net writes: Thanks for the feedback Lynn. Unusual to see a "poor port design" actually= aid performance. =20 Mike Wills =20 =20 It is not obvious until you start graphing the open and close events, but= the side port which uses the side of the rotor as a shutter to open and= close the port, offers Mazda great latitude in port timing. In the perip= hery ported engine (both ports) it is impossible to arrive at zero overlap= , and have an engine that will produce any power at all. The apex seal doe= s not close off either port at all, it just valves gasses in one direction= or another.=20 =20 In addition, the overlap of the periphery ported engine is far more effect= ive flow wise than overlap in the side ported engine. One apex seal is abo= ve the intake port when the opposing apex seal is below the exhaust port.= Flow between the two is unobstructed. =20 So, at low RPM you get fresh mixture leaving through the exhaust port, and= combinations of burned and unburned fuel and exhaust gasses flowing partw= ay back into the intake runners. =20 This reduces the low RPM output to the point that the engine seems quit do= cile, and is easy to drive around in the car, slowly, or possibly taxi in= an aircraft. This would make off idle tuning data useless as there will= be fuel burning right on top of the EGT probes, and unburned fuel reachin= g the F/A sensor. =20 =20 The engine will act along the lines of a piston engine with a long duratio= n cam. When the engine reaches its happy RPM where all of the mixture is= burning inside the engine, it will step up on the "CAM" and you will see= what a good idea this was. Use slow throttle inputs until you find the "W= OW" RPM, and be ready with all available rudder.=20 =20 When we first ran a factory periphery port engine, we found that there wer= e places on the track that would not allow full throttle. This with 11" wi= de slicks. Thank Heaven for rev limiters. The driver reported the rear end= getting real loose cresting hills and bumps. =20 Why yes it was.......... =20 Lynn E. Hanover=20 ----------MB_8CCDFA9F01A23F2_291C_D74A_webmail-m081.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"
Bryan,
As a reference the original Powersport 13B P-port is rated at 210 HP= normally aspirated. The fuel flows are very similar to any other engine= producing that level of power. Steve tells me that they were seeing FF ve= ry comparable to an angle valve IO-360 producing identical power. This eng= ine was dynoed with butterfly valves in the housing. These p-ports we= re 1-5/8' diameter optimized for 6000 RPM. The engine would rev higher but= you were already at peak power anyway. Larger ports will make more power= at higher RPM. Tuning will become more critical with the larger port= s. A personal anecdote here. I built a high reving motorcycle engine in 19= 78 with all the "best" parts at the time. The engine was unreal at high re= vs, but if you transitioned to anything below 4000 RPM by shutting the thr= ottle off and quickly opening it again the engine would "catch" or hi= t an RPM plateau and would rev no higher. In fact the engine would di= e if not returned to idle! This horrible malfunction was TUNED OUT later,= and the solution was surprisingly simple, however difficult to find. = ;The key here is that many people underestimate the job of installing and= tuning p-ports. There are two aspects, first the initial install being su= re there are no leaks . Then second, and most overlooked is that the syste= m must tolerate the heat cycles of a high power engine without DEVELOPING= NEW LEAKS for a long time. Powersport used an insert with o-rings sealing= the port. O-rings or other elastomers work much better than epoxy on long= -term sealing because there are different expansion rates between the port= and the epoxy. On a car you can usually get away with epoxy for a wh= ile. An aircraft is a different animal. The aircraft engine needs to= tolerate 80-100% power for long periods and then long cold-soaks on= the ground. The rotary is mechanically tough enough but you need to desig= n your subsystems like a race car that will see a 500 mile long strai= ght-away!  When Paul Lamar ran one of the newsletter guys P-port Rene= sis at MazdaTrix, They got great numbers, but only after changing to an in= take that MazdaTrix had spent lots of time tuning. P-ports will run great,= and even idle well if not too oversized, but don't expect the tuning to= be real easy. Remember you are designing a new intake, exhaust, and the= equivilent of a new cam timing all at once. The rotary is very much like= a two-cycle in that respect. The results can be very worth while if you= understand the difficulty involved.
Bill Jepson



-----Original Message-----
From: George Lendich <lendich@aanet.com.au>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, Jun 21, 2010 2:36 pm
Subject: [FlyRotary] Re: 13B rotary engines

 Bryan,
Not all P-ports are equal.
More power =3D more fuel.
Talk to Bill Jepson ( on here) about avai= lability of new P-ports.
George ( down under).
All this talk of ad= ditional power coupled with an easier intake design has me thinking I shou= ld probably go this direction with my Renesis.  It=E2=80=99s still on= the stand after rebuild.
I haven=E2=80=99t= constructed the manifold yet anyway.
 
I assume fuel flow= will be higher than normal?
 
Is slide throttle= best option?
 
Need to search arch= ives I guess.
 
Good info Lynn, Tha= nks
 
Bryan=
 
 
 
 
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover
Sent: Monday, June 21, 201= 0 12:15 PM
To: Rotary motors in aircr= aft
Subject: [FlyRotary] Re:= 13B rotary engines
 
In a message dated 6/21/2010 11:03:01 A.M. Eastern St= andard Time, rv-4mike@cox.net writ= es:
Thanks for= the feedback Lynn. Unusual to see a "poor port design" actually aid perfo= rmance.
 
Mike Wills<= /SPAN>
 
 
It is not obvious until you start graphing the open= and close events, but the side port which uses the side of the rotor as= a shutter to open and close the port, offers Mazda great latitude in port= timing.  In the periphery ported engine (both ports) it is impossibl= e to arrive at zero overlap, and have an engine that will produce any powe= r at all. The apex seal does not close off either port at all, it just val= ves gasses in one direction or another.
 
In addition, the overlap of the periphery ported engi= ne is far more effective flow wise than overlap in the side ported engine.= One apex seal is above the intake port when the opposing apex seal is bel= ow the exhaust port. Flow between the two is unobstructed.
 
So, at low RPM you get fresh mixture leaving through= the exhaust port, and combinations of burned and unburned fuel and exhaus= t gasses flowing partway back into the intake runners.
 
This reduces the low RPM output to the point that the= engine seems quit docile, and is easy to drive around in the car, slowly,= or possibly taxi in an aircraft.  This would make off idle tuning da= ta useless as there will be fuel burning right on top of the EGT probes,= and unburned fuel reaching the F/A sensor. 
 
The engine will act along the lines of a piston= engine with a long duration cam. When the engine reaches its happy RPM wh= ere all of the mixture is burning inside the engine, it will step up on th= e "CAM" and you will see what a good idea this was. Use slow throttle inpu= ts until you find the "WOW" RPM, and be ready with all available rudder.=
 
When we first ran a factory periphery port engine, we= found that there were places on the track that would not allow full throt= tle. This with 11" wide slicks. Thank Heaven for rev limiters. The driver= reported the rear end getting real loose cresting hills and bumps.=
 
Why yes it was..........
 
Lynn E. Hanover 
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