X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-m25.mx.aol.com ([64.12.137.6] verified) by logan.com (CommuniGate Pro SMTP 5.1c.1) with ESMTP id 1212886 for flyrotary@lancaironline.net; Thu, 29 Jun 2006 20:59:14 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.137.6; envelope-from=Lehanover@aol.com Received: from Lehanover@aol.com by imo-m25.mx.aol.com (mail_out_v38_r7.5.) id q.53e.1d5619c (48624) for ; Thu, 29 Jun 2006 20:58:29 -0400 (EDT) From: Lehanover@aol.com Message-ID: <53e.1d5619c.31d5d134@aol.com> Date: Thu, 29 Jun 2006 20:58:28 EDT Subject: Re: [FlyRotary] Re: Damage To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1151629108" X-Mailer: 9.0 Security Edition for Windows sub 5319 X-Spam-Flag: NO -------------------------------1151629108 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 6/29/2006 6:32:46 P.M. Eastern Daylight Time, lendich@optusnet.com.au writes: It has been suggested to me that 140 degree is the upper limit of inlet air temperature before detonation occurs.I guess this is a guide to a turbo inter cooler application. Again as you say, compression varies this, I didn't think of advance and the accompanying variable volumetric efficiency between idle and high rpm affecting compression. Why don't the big boys run air conditioning units to cool the intake - does it suck-up too much HP? George By the "Big boys you mean airplane engine? They all (all of the turbo engines) do run inter coolers. In the hand book for those airplanes there would be some of the data you seek. The 93-95 Mazda had a large inter cooler, and the first big hop up item added is a bigger inter cooler. The engines tolerance to Detonation (charge temperature) is a function of its construction, chamber shape and detailing. The rotary with a large cool surfaces in the chamber is not prone to detonation. Not until the coolant temps and oil temps become too high and the mixture is just right, (just rich of peak EGT and the timing is just a bit too advanced. Anyone who gives you a hard number for any of these values..............well, don't buy anything off of him. If one value is just a hair too low then another value will have to be way over the line to get detonation. It cannot be one thing alone. Sort of a team effort if you will. A combination of values that occurred on that occasion. Suppose there was an instance of detonation that was detected by a Lambda sensor. If we are recovering a number of values from the engine and can download them to a screen, we can see the exact combination that produced that event. It could happen again tomorrow with a different set of values. This is done in racing all of the time. Then lay these values from yesterday over today's and see what changed. If the temps are even marginally under control, it won't happen. So, one day, 140 might be OK, and the next day something else changes and 140 is too much. The street racers add water to the intake at high boost numbers. They tune very rich at high boost. The timing may be close or into minus numbers at high boost. They spray water on the inter coolers, oil coolers and water radiators at high boost. Do we see a pattern forming here? They take away waste heat any way they can with special attention to induction (charge temperature) tract temps. Lynn E. Hanover Lynn, -------------------------------1151629108 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 6/29/2006 6:32:46 P.M. Eastern Daylight Time,=20 lendich@optusnet.com.au writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>
It has been sug= gested=20 to me that 140 degree is the upper limit of inlet air temperatur= e=20 before detonation occurs.I guess this is= a=20 guide to a turbo inter cooler=20 application.
Again as you sa= y,=20 compression varies this, I didn't think of advance and the accompanying=20 variable volumetric efficiency between idle and high rpm affecting=20 compression.
Why don't the b= ig=20 boys run air conditioning units to cool the intake - does it suck-up too m= uch=20 HP?
George
By the "Big boys you mean airplane engine? They all (all of the turbo=20 engines) do run inter coolers. In the hand book for those airplanes there wo= uld=20 be some of the data you seek.
 
The 93-95 Mazda had a large inter cooler, and the first big hop up item= =20 added is a bigger inter cooler.
 
The engines tolerance to Detonation (charge temperature) is a=20 function  of its construction, chamber shape and detailing. The rotary=20= with=20 a large cool surfaces in the chamber is not prone to detonation.
 
Not until the coolant temps and oil temps become too high and the mixtu= re=20 is just right, (just rich of peak EGT and the timing is just a bit too advan= ced.=20 Anyone who gives you a hard number for any of these values..............well= ,=20 don't buy anything off of him.
 
If one value is just a hair too low then another value will have to be=20= way=20 over the line to get detonation. It cannot be one thing alone. Sort of a tea= m=20 effort if you will. A combination of values that occurred on that occasion.=20 Suppose there was an instance of detonation that was detected by a Lambda=20 sensor. If we are recovering a number of values from the engine and can down= load=20 them to a screen, we can see the exact combination that produced that=20 event.
It could happen again tomorrow with a different set of values. This is=20= done=20 in racing all of the time. Then lay these values from yesterday over today's= and=20 see what changed.
 
If the temps are even marginally under control, it won't happen. So, on= e=20 day, 140 might be OK, and the next day something else changes and 140 is too= =20 much.
 
The street racers add water to the intake at high boost numbers. They t= une=20 very rich at high boost. The timing may be close or into minus numbers at hi= gh=20 boost. They spray water on the inter coolers, oil coolers and water=20 radiators at high boost.  
 
Do we see a pattern forming here? They take away waste heat any way the= y=20 can with special attention to induction (charge temperature) tract temps.
 
Lynn E. Hanover
 
    
 
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>
<= /FONT> 
Lynn,
 
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