X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=VR+/t1Yj4tZD3VhNnkAgtQ==:117 a=x7bEGLp0ZPQA:10 a=Fee85h93u3AA:10 a=_RQrkK6FrEwA:10 a=cwU5pYxC-w0A:10 a=Ia-xEzejAAAA:8 a=7g1VtSJxAAAA:8 a=7ff2tePFqyfsA8v7RhAA:9 a=6RkFjMlk4fhPYdi7:21 a=XwatsUqMNPmQflw6:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=PVo5WVmunYBfAmhM:21 a=bIdOfSkPg1IRdGeT:21 a=F3g0kE-TQYHeX9zQ:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=grOzbf7U_OpcSX4AJOnl:22 a=pHzHmUro8NiASowvMSCR:22 a=nt3jZW36AmriUCFCBwmW:22 From: "lehanover lehanover@aol.com" Received: from sonic308-3.consmr.mail.bf2.yahoo.com ([74.6.130.42] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 541542 for flyrotary@lancaironline.net; Sat, 18 Jul 2020 00:27:13 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.6.130.42; envelope-from=lehanover@aol.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aol.com; s=a2048; t=1595046416; bh=0XGLOpqZVcIc+RX0/rhaD774PU23wDSoRvOFuq8XdlU=; h=Date:From:To:In-Reply-To:References:Subject:From:Subject; b=iZcbDDItW8kaAJvpzAseal+U9WOOUZy3mKcY+QDub4mOa3KmD0YxtR8EEOwsX0oc6n4+c/5H+RP1UHMqUSU2DyPvVYgRm/Y7dbIWc4dQkoG4oO8FothLykg4fdcJEPqzqh/7vtmDH4PXHzdy2knvyKg0WaZaJP6WzIIkvMDDSWiQdmlszYHgTRejOXCDbEZcnicM1hMWRwaGbqpSt5SsFVnhs0vS7YhjJj5Di07Yc8EFkxVFfKeBszlo09Np6fNUe2VoANmaKcGvF6+xEe/PUFqalrAU4pUegte2fJpKE0H1uGvMB+G3IweiEJ3+yckvfhXbP/JzLZDVCHOUOGEQHQ== X-YMail-OSG: A.8UElsVM1kdvhLx498oo1sx4PIKE7e6YFJJKZoHyvplZEKHvwJYzw2q1Wft3iS l.fZU8SzkwC5U.sdeN.Hlngy21BUX6GTtT3AJNT7QqNGjPhOm2y1ltxrS05XjYMxVsomjTXZA7X0 nMoDBFj8kesFkJUf.mLU_96ZM27KTpm8KHmua4C1E89OEptqB7XNBpkQ9tWGRIj.hSidiEWJaCaX CGXcu28Ndp9S2p7Z.pcmnhyNOaLRUYhnClUF.t3ZHEIRyskI8iLBfKLKwkYBBni36zOq2hdd.aIw 5VpCYdaQ5eeycrBpGxSElo6HcPWJooPc5ah75gd.ePzR.7gC6yWOuLVAPLLQ1wI9AETIdPTt8KUy XTXsAVCpKaMatObCzws.2ObmxgPAkdg8iQnTfhp2uU_87rQlpY2X31NAahQ22jjFPXLKa18fBVNZ uTp7QFSmvgrD9urd_4Yk4HUYEpF175Mrv.marRZmK2YAC7Lu896D2B.41G5JldhJbf5IuuDz5oMq tUNjwT8n9wWKQ9Itjjwh1rrF5Hr91ykyXpv__78znamRHnmtamekgoc7piXRaf6jsZE.1D5YOWqE Lche8Dx8eSSiAhbEeulqL4Fl5dKqYIkKp4g648MQzVAsCp9gE5nPBoSaBLI0KFrS.47VoWUgPFov ZqqolwP.WCBOs87Va0q_gCQFdrpPKFdQL8CtasfsNjiT9eeN8Reeur2XXpdBr5BrApNoaM153Ezw VoipzMM8I14rSUwwb8yLnlt04EvOXw5UbgSsXFexPFcTmNCJ.YF4P36gCxPY5GbiiU5mwE4lbmfi 5oxh_X72Oap3SrgVSbx0d9BAvKqZsrWQyrJ6CQqP7hakXJJ.rw9R4LnyKlgHmIeivSauKqI8SPhQ WVe4qGAu_71Z99zYQz3itQRGFtBCrHdl9k4cLJsSRhGvqP0XV3bvO0q64JR1mE2Y9V59CHpCurS7 PahGAbuIcsY_C1oH0Ge_02YwHT5fAvcIxhXkbmznxor0Ka48snbeJJr.EiUoSjXb19SRdVnGC2d7 nhl1DsFiWPmZEltiICTv4eNXqphhJ_nrJ1Z_wqyj8EOYc6Y2tITkqBDDYW7lN3T1mwCckIqhHF9W oAsr7RDjrd2aC_LuKmE_05vPk9LpSPF2D2MHxAqoCzdlBuWIZvwCSjd4CE76efHCXiUxtWVcFZA4 n5VJ_9NGwMUeNzjwKPN2SyvqmoEdG.lUi2McM7YFx5Z45MUAM6IoF9YHVvhAkFfVAD5Sbk.y1jk6 0jf3AE2.7auBSBeBWlNdnJ05K2dQ0pwkrlKQg2QFPLC4HhDn.usWGEUiqw6GRl_gt5AVJ Received: from sonic.gate.mail.ne1.yahoo.com by sonic308.consmr.mail.bf2.yahoo.com with HTTP; Sat, 18 Jul 2020 04:26:56 +0000 Date: Sat, 18 Jul 2020 04:26:55 +0000 (UTC) To: flyrotary@lancaironline.net Message-ID: <265857733.2484074.1595046415663@mail.yahoo.com> In-Reply-To: References: Subject: Re: [FlyRotary] over square and detonation of a rotary for my pilot friend MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_2484073_1220020479.1595046415661" X-Mailer: WebService/1.1.16271 aolloki Apache-HttpClient/4.5.7 (Java/1.8.0_252) Content-Length: 10787 ------=_Part_2484073_1220020479.1595046415661 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Under square, over square or square (Bore and stroke the same number) matte= rs not. Detonation is the ignition event remote from the spark plug AFTER t= he plug has fired at its normal time. So, detonation is charge temperate dependent. Although my driver could detonate the race engine on the way to the false g= rid and he did observe the rules of detonation by letting the clutch all th= e way out (Engaged) while at very low speed. Our first gear was good for 70= MPH, (Like starting out in third gear in a street car) So you must slip th= e clutch a bit and then declutch to clear the engine, then slip some more. = But never engage the clutch with any amount of throttle applied. In normal use it is nearly impossible to detonate a normally aspirated rota= ry. Large cold combustion with poor squish areas.This is also why they are = hard to start in cold weather. Worse when warn out with low compression. The fuel air mixture is carried past the plugs at high speed. Like you hold= ing a lighter out the window going one way down the road while your friend = passes you in the opposite direction holding a candle out his window.The ch= ance of the candle lighting is slim indeed. The engine will run very well on very low octane fuel. In olden times we ra= n 86 octane (regular) gas with extra motor oil mixed with the fuel so as to= reduce the octane further and improve sealing and reduce ware.Timing at 20= degrees on both leading and trailing plugs. =20 Later race engines used 27 degrees of advance on both plugs but still regul= ar gas. The ignition system in racers is nearly always a MSD 6AL or better = or a Mallory HiFire. My plugs were gaped at .010" NGK R6725-11.5. If a high= speed miss developed (Above 9,500 RPM) the plug gap had opened a bit. The rotary is a popular subject of the boosted folks because it can be boos= ted without fear of detonation, most of the time.But remember that charge t= emperature must be controlled. This means anything that overheats the charg= e must be controlled. So boosting above 4 or 5 pounds without an intercoole= r is not done because of "Heat of compression. Full throttle from idle is n= ot done suddenly. (unless you have control of ignition advance via computer= ). Ignition advance must be reduced as boost pressure goes up. Notice that as boost goes up the engine (in effect)= is getting bigger in displacement=C2=A0 but he combustion chamber is not. = So the effect is that the compression ratio going up. And, since flame fron= t travel will be higher, the effect is that you are advancing the timing...= .ouch. That is the why of it.....Now the How of it..........Biggest intercooler yo= u can fit in.....Highest octane fuel you can afford.=C2=A0 Well rich of pea= k EGT for take off and climb. Once at cruise, lean to lean of peak until le= an stumble, then back a bit. Looking for EGTs around 1600 degrees. Water of= coolant about 180. Oil about 180 to 190. Make one change at a time. Make the change big enough to see which way you = are moving. Make a movie of the gages......LEH=C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0=20 In a message dated 7/17/2020 8:10:17 PM Eastern Standard Time, flyrotary@la= ncaironline.net writes: Hi people. My test pilot friend and I are continuing our journey of extending the phas= e#1 envelope and now experimenting with engine settings.With a flight adjus= table prop he is asking questions about 'over square' and detonation. Can a= nyone give me an answer for him? Thanks Steve IzettGlasaie Super IIRG Renesis 4 port RD1C variable pitch prop. --Homepage:=C2=A0 http://www.flyrotary.com/Archive and UnSub:=C2=A0 http://= mail.lancaironline.net:81/lists/flyrotary/List.html ------=_Part_2484073_1220020479.1595046415661 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit
Under square, over square or square (Bore and stroke the same number) matters not. Detonation is the ignition event remote from the spark plug AFTER the plug has fired at its normal time.
So, detonation is charge temperate dependent.

Although my driver could detonate the race engine on the way to the false grid and he did observe the rules of detonation by letting the clutch all the way out (Engaged) while at very low speed. Our first gear was good for 70 MPH, (Like starting out in third gear in a street car) So you must slip the clutch a bit and then declutch to clear the engine, then slip some more. But never engage the clutch with any amount of throttle applied.

In normal use it is nearly impossible to detonate a normally aspirated rotary. Large cold combustion with poor squish areas.
This is also why they are hard to start in cold weather. Worse when warn out with low compression.

The fuel air mixture is carried past the plugs at high speed. Like you holding a lighter out the window going one way down the road while your friend passes you in the opposite direction holding a candle out his window.
The chance of the candle lighting is slim indeed.

The engine will run very well on very low octane fuel. In olden times we ran 86 octane (regular) gas with extra motor oil mixed with the fuel so as to reduce the octane further and improve sealing and reduce ware.
Timing at 20 degrees on both leading and trailing plugs.

Later race engines used 27 degrees of advance on both plugs but still regular gas. The ignition system in racers is nearly always a MSD 6AL or better or a Mallory HiFire. My plugs were gaped at .010" NGK R6725-11.5. If a high speed miss developed (Above 9,500 RPM) the plug gap had opened a bit.

The rotary is a popular subject of the boosted folks because it can be boosted without fear of detonation, most of the time.
But remember that charge temperature must be controlled. This means anything that overheats the charge must be controlled. So boosting above 4 or 5 pounds without an intercooler is not done because of "Heat of compression
. Full throttle from idle is not done suddenly. (unless you have control of ignition advance via computer). Ignition advance must be reduced as
boost pressure goes up. Notice that as boost goes up the engine (in effect) is getting bigger in displacement  but he combustion chamber is not. So the effect is that the compression ratio going up. And, since flame front travel will be higher, the effect is that you are advancing the timing....ouch.

That is the why of it.....Now the How of it..........Biggest intercooler you can fit in.....Highest octane fuel you can afford.  Well rich of peak EGT for take off and climb. Once at cruise, lean to lean of peak until lean stumble, then back a bit. Looking for EGTs around 1600 degrees. Water of coolant about 180. Oil about 180 to 190.

Make one change at a time. Make the change big enough to see which way you are moving. Make a movie of the gages......LEH         

In a message dated 7/17/2020 8:10:17 PM Eastern Standard Time, flyrotary@lancaironline.net writes:

Hi people.

My test pilot friend and I are continuing our journey of extending the phase#1 envelope and now experimenting with engine settings.
With a flight adjustable prop he is asking questions about 'over square' and detonation.
Can anyone give me an answer for him?

Thanks

Steve Izett
Glasaie Super IIRG Renesis 4 port RD1C variable pitch prop.





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