Return-Path: Received: from [65.54.241.203] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.2.2) with ESMTP id 421681 for flyrotary@lancaironline.net; Sun, 19 Sep 2004 17:06:06 -0400 Received-SPF: none receiver=logan.com; client-ip=65.54.241.203; envelope-from=lors01@msn.com Received: from hotmail.com ([65.54.169.58]) by hotmail.com with Microsoft SMTPSVC(5.0.2195.6713); Sun, 19 Sep 2004 14:05:35 -0700 Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 19 Sep 2004 14:05:35 -0700 Received: from 65.54.98.110 by bay3-dav28.bay3.hotmail.com with DAV; Sun, 19 Sep 2004 21:05:35 +0000 X-Originating-IP: [65.54.98.110] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Renesis Temps, Lynn? Date: Sun, 19 Sep 2004 17:05:35 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00A8_01C49E6A.E100E230" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MimeOLE: Produced By MSN MimeOLE V9.10.0006.2205 Seal-Send-Time: Sun, 19 Sep 2004 17:05:35 -0400 Message-ID: X-OriginalArrivalTime: 19 Sep 2004 21:05:35.0859 (UTC) FILETIME=[68790C30:01C49E8C] Return-Path: lors01@msn.com This is a multi-part message in MIME format. ------=_NextPart_000_00A8_01C49E6A.E100E230 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I'm no expert by any means, but the higher water temps do not = surprise me. As I understand it, the exhaust porting on the Renesis is=20 completely different than the 13B. The exhaust runs much cooler in the = Renesis because of this, so I'm told. It is likely that a significant=20 fraction of the heat that is not going into the exhaust is going into = the=20 water jacket instead. True, the EGTs on the Renesis are much lower (by about 250 degrees) = but the reduction is supposed to be due to a combination of less = unburned fuel in exhaust, later opening of exhaust ports and higher = compression ratio. These should all result in better fuel efficiency = and power. But yes, part of the heat is apparently finding it's way = into the coolant unless I have missed something. The car folks probably won't sense much of a change in water = temps=20 because they typically have a lot of margin in the cooling system. = You, on=20 the other hand, have a cooling system that has very little (if any) = extra=20 capacity. True, but I was hoping some of the racing crowd (who don't usually run = thermostats) had swapped a Renesis into an existing car and perhaps seen = a coolant temp change like I did. Or maybe a dyno operator who noticed = a higher coolant temp rise through the block. I haven't seen anyone do this, but I would think that it = would=20 help the cooling if an effort were made to course the cowl air close = to the=20 engine cases and/or the oil pan instead of just letting it blow = anywhere it=20 pleases inside the cowling. A finned (or ribbed) oil pan might help = too=20 without adding much weight. Believe me, in an RV-4 cowl, the air has no choice but to pass closely = over the engine & pan. There's no other place for it to go : ) It sounds like you are not after much additional cooling, so = small=20 changes like these might be enough. Bill Dube' Actually, it's a big bucket load of cooling. Calculate the energy = required to heat 30 GPM of coolant by 15 degrees. =20 Figured out a way to test the exhaust heat theory. I'm installing a = temp sensor in the engine heater port. This is after the coolant has = passed over the combustion chambers but before going around the exhaust = ports. My existing coolant temp sensor is positioned at the water pump = housing outlet which is after both. The delta temp should represent = the heat added by the exhaust. Tracy >> Homepage: http://www.flyrotary.com/ >> Archive: = http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_00A8_01C49E6A.E100E230 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 

         I'm no = expert by any=20 means, but the higher water temps do not
surprise=20 me.

         As I = understand=20 it, the exhaust porting on the Renesis is
completely different = than the=20 13B. The exhaust runs much cooler in the
Renesis because of this, = so I'm=20 told. It is likely that a significant
fraction of the heat that is = not=20 going into the exhaust is going into the
water jacket = instead.
True, the EGTs on the Renesis are much = lower (by=20 about 250 degrees) but the reduction is supposed to be due to a = combination of=20 less unburned fuel in exhaust, later opening of exhaust ports and = higher=20 compression ratio.  These should all result in better fuel = efficiency and=20 power.   But yes, part of the heat is apparently finding = it's way=20 into the coolant unless I have missed something.
 

         The car = folks=20 probably won't sense much of a change in water temps
because they=20 typically have a lot of margin in the cooling system. You, on
the = other=20 hand, have a cooling system that has very little (if any) extra=20
capacity.
True, but I was hoping some of the racing = crowd (who=20 don't usually run thermostats) had swapped a Renesis into an = existing car=20 and perhaps seen a coolant temp change like I did.  Or maybe a = dyno=20 operator who noticed a higher coolant temp rise through the=20 block.

         I haven't = seen=20 anyone do this, but I would think that it would
help the cooling = if an=20 effort were made to course the cowl air close to the
engine cases = and/or=20 the oil pan instead of just letting it blow anywhere it
pleases = inside the=20 cowling. A finned (or ribbed) oil pan might help too
without = adding much=20 weight.
 
Believe me, in an RV-4 cowl, the air has no = choice=20 but to pass closely over the engine & pan.  There's no other = place=20 for it to go : )

         It = sounds like=20 you are not after much additional cooling, so small
changes like = these=20 might be = enough.

         Bill=20 Dube'
Actually, it's a big bucket load of=20 cooling.   Calculate the energy required to heat 30 GPM = of=20 coolant by 15 degrees. 
 
Figured out a way to test the exhaust heat=20 theory.  I'm installing a temp sensor in the engine heater=20 port.  This is after the coolant has passed over the combustion = chambers=20 but before going around the exhaust ports.  My existing coolant = temp=20 sensor is positioned at the water pump housing outlet which is after=20 both.   The delta temp should represent the heat added by = the=20 exhaust.
 
Tracy




>>  Homepage:  http://www.flyrotary.com/
>&= gt; =20 Archive:   http://lancai= ronline.net/lists/flyrotary/List.html
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