X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from omr-m01.mx.aol.com ([64.12.143.75] verified) by logan.com (CommuniGate Pro SMTP 6.0.5) with ESMTPS id 6396996 for flyrotary@lancaironline.net; Tue, 30 Jul 2013 14:17:22 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.143.75; envelope-from=Lehanover@aol.com Received: from mtaomg-da05.r1000.mx.aol.com (mtaomg-da05.r1000.mx.aol.com [172.29.51.141]) by omr-m01.mx.aol.com (Outbound Mail Relay) with ESMTP id 1694F7008E582 for ; Tue, 30 Jul 2013 14:16:50 -0400 (EDT) Received: from core-moa005b.r1000.mail.aol.com (core-moa005.r1000.mail.aol.com [172.29.233.17]) by mtaomg-da05.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id DE869E000081 for ; Tue, 30 Jul 2013 14:16:49 -0400 (EDT) From: Lehanover@aol.com Full-name: Lehanover Message-ID: Date: Tue, 30 Jul 2013 14:16:49 -0400 (EDT) Subject: Fwd: [FlyRotary] Re: : Misfire To: flyrotary@lancaironline.net MIME-Version: 1.0 X-Mailer: AOL 9.0 VR sub 5203 Content-Type: multipart/mixed; boundary="-----------------------------1375208209" X-Originating-IP: [184.57.119.231] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1375208210; bh=iEd3v+UvVeKEvx3RM6YILNh5SDjgvBibDovj/nTxbz8=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=vdITIsqn+TerkN70P0MshZlxAgix0jbHlSzx0ynzDsuaAHHQ53izLyx4ABQoZkQhy SO7UzlOixAXo33ulkirdXu9I0t0Os+HmhxH4fVCE4lHU2wVvDK7K6aGBa/rKrOGiHq JsNBYP1zD4siAKeAdSfEsTlNYaPiNJeORqxLClfI= x-aol-sid: 3039ac1d338d51f803117c8e -------------------------------1375208209 Content-Type: multipart/alternative; boundary="part1_a2691.3539d264.3f295d11_boundary" --part1_a2691.3539d264.3f295d11_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 7/30/2013 1:36:12 P.M. Eastern Daylight Time, Lehanover@aol.com writes: The rotary has three features that make for a poor idle compared to a piston engine. Heat of compression. The rise in chamber temperature caused by compressing the fuel/air mixture. The rotary has poor heat of compression because of the large surface are of the chamber, and much of the chamber surface is cooled. Low heat of compression allows fuel droplets to condense on the chamber surfaces and the engine sees this as a mixture that is too lean to light. Compression leakage: The rotor face has many end gaps through which it leaks compression. For example, on NA rotaries I gap the side seal to corner seal at zero. So long as the combination of two side seals and the joining corner seal pop back up when depressed and released, that is sufficient. The zero gap will become a measurable gap shortly after break in. Overly wide end gaps lead to leakage of compression, and that leads to lowered heat of compression as above. Effective compression ratio: At idle and near idle, the amount of air allowed into the engine is minimal. So the computer limits the injection pulse width accordingly.So the cylinder filling is minimal, and so heat of compression is minimal. So, if the same amount of cylinder filling is used. The rotor with the higher compression ratio will generate fewer misses and a smoother idle. Because for a fixed cylinder filling number, the higher compression rotor produces the highest heat of compression. Higher heat of compression means better fuel vaporization and a more thorough burn. A misfire is an event wherein a dose or part of a dose of mixture was not lighted at or near the correct time during the cycle. A misfire that involves no burned mixture is a noticeable event, in that the engine will be out of balance for that cycle. The engine will wiggle in its mount. A misfire that involves a trailing plug will not be noticed at or near idle. A misfire that involves the leading plug can be noticed by the very attentive. A popping sound in the headers or exhaust in general with no engine wiggle is more likely a small air leak in the header, that allows oxygen to mix in the header with some as yet unburned fuel. The popping is this mixture igniting. Very likely to be experienced on long closed throttle descents. A misfire at higher throttle settings and full power, will be very noticeable, as an unlighted charge between two lighted charges will produce quite an imbalance jerk in the engine, and the mixture from the misfire will light in the header right outside the engine. So you get a jerk and a loud change in engine tone. This does not damage the engine, but can damage the exhaust system and, or, ruin a muffler. As has been seen, a damaged muffler can stop an engine or reduce it's power out put to useless levels. Lynn E. Hanover --part1_a2691.3539d264.3f295d11_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 7/30/2013 1:36:12 P.M. Eastern Daylight Time,=20 Lehanover@aol.com writes:
=
The rotary has three features that make for a poor idle=20 compared to a piston engine.
 
Heat of compression.
The rise in chambe= r temperature=20 caused by compressing the fuel/air mixture.
The rotary has poor heat of compression because of the large surface= are=20 of the chamber, and much of the chamber surface is cooled. Low heat of=20 compression allows fuel droplets to condense on the chamber surfaces and = the=20 engine sees this as a mixture that is too lean to light.
 
Compression leakage:
The rotor face has= many end=20 gaps through which it leaks compression.
&nbs= p;
For example, on NA= rotaries I=20 gap the side seal to corner seal at zero. So long as the combination of two= side=20 seals and the joining corner seal pop back up when depressed and released, = that=20 is sufficient. The zero gap will become a measurable gap shortly after brea= k in.=20 Overly wide end gaps lead to leakage of compression, and that leads to lowe= red=20 heat of compression as above.
 
Effective compression ratio:
 
At idle and near idle, the amount of air allowed into the engine is=20 minimal. So the computer limits the injection pulse width accordingly.So th= e=20 cylinder filling is minimal, and so heat of compression is minimal.
 
So, if the same amount of cylinder filling is used. The rotor with the= =20 higher compression ratio will generate fewer misses and a smoother idle. Be= cause=20 for a fixed cylinder filling number, the higher compression rotor prod= uces=20 the highest heat of compression. 
 
Higher heat of compression means better fuel vaporization and a more= =20 thorough burn.
 
A misfire is an event wherein a dose or part of a dose of mixture was = not=20 lighted at or near the correct time during the cycle.
A misfire that involves no burned mixture is a noticeable event, in th= at=20 the engine will be out of balance for that cycle. The engine will wiggle in= its=20 mount. A misfire that involves a trailing plug will not be noticed at or ne= ar=20 idle. A misfire that involves the leading plug can be noticed by the very= =20 attentive.
 
A popping sound in the headers or exhaust in general with no engine wi= ggle=20 is more likely a small air leak in the header, that allows oxygen to mix in= the=20 header with some as yet unburned fuel. The popping is this mixture igniting= .=20 Very likely to be experienced on long closed throttle descents.
 
A misfire at higher throttle settings and full power, will be very=20 noticeable, as an unlighted charge between two lighted charges will produce= =20 quite an imbalance jerk in the engine, and the mixture from the misfir= e=20 will light in the header right outside the engine. So you get a jerk and a = loud=20 change in engine tone.
This does not damage the engine, but can damage the exhaust system and= ,=20 or, ruin a muffler. As has been seen, a damaged muffler can stop an en= gine=20 or reduce it's power out put to useless levels.
 
Lynn E. Hanover
 
 
--part1_a2691.3539d264.3f295d11_boundary-- -------------------------------1375208209 Content-Type: message/rfc822 Return-Path: Received: from core-moa005b.r1000.mail.aol.com (core-moa005.r1000.mail.aol.com [172.29.233.17]) by mtaomg-mb03.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 69E2CE000086 for ; Tue, 30 Jul 2013 13:36:12 -0400 (EDT) From: Lehanover@aol.com Full-name: Lehanover Message-ID: Date: Tue, 30 Jul 2013 13:36:12 -0400 (EDT) Subject: Re: [FlyRotary] Re: : Misfire To: Lehanover@aol.com MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_a15a3.173af8f9.3f29538c_boundary" X-Mailer: AOL 9.0 VR sub 5203 X-Originating-IP: [184.57.119.231] x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1375205772; bh=RNYAqHpnci5vQy7res8DEJsm7wKhTJRY59Zwl3UjDr0=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=BB5KBa53373HyJkF2n8+foznMC8qPQtbVPRzDMhw6kBuUVfHZ+zOADXXPXPgPWPv4 EZE5j6fzpmDoaYagc2Yz94GTUeukqZUmu/fLuBTRMnpwzpNa60TAePjLcVOwtDAHfC oyYIbrJG/22Kq12JJjm21O9Msrx3fYeNKQf1JwZ0= X-AOL-SCOLL-SCORE: 0:2:446623296:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d294a51f7f98c5bd0 --part1_a15a3.173af8f9.3f29538c_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit The rotary has three features that make for a poor idle compared to a piston engine. Heat of compression. The rise in chamber temperature caused by compressing the fuel/air mixture. The rotary has poor heat of compression because of the large surface are of the chamber, and much of the chamber surface is cooled. Low heat of compression allows fuel droplets to condense on the chamber surfaces and the engine sees this as a mixture that is too lean to light. Compression leakage: The rotor face has many end gaps through which it leaks compression. For example, on NA rotaries I gap the side seal to corner seal at zero. So long as the combination of two side seals and the joining corner seal pop back up when depressed and released, that is sufficient. The zero gap will become a measurable gap shortly after break in. Overly wide end gaps lead to leakage of compression, and that leads --part1_a15a3.173af8f9.3f29538c_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
The rotary has three features that make for a poor idle comp= ared=20 to a piston engine.
 
Heat of compression. The rise in chamber temperature caused by compres= sing=20 the fuel/air mixture.
The rotary has poor heat of compression because of the large surface a= re of=20 the chamber, and much of the chamber surface is cooled. Low heat of compres= sion=20 allows fuel droplets to condense on the chamber surfaces and the engine see= s=20 this as a mixture that is too lean to light.
 
Compression leakage: The rotor face has many end gaps through which it= =20 leaks compression. For example,
on NA rotaries I gap the side seal to corner seal at zero. So long as = the=20 combination of two side seals and the joining corner seal pop back up when= =20 depressed and released, that is sufficient. The zero gap will become a=20 measurable gap shortly after break in. Overly wide end gaps lead to leakage= of=20 compression, and that leads  
 --part1_a15a3.173af8f9.3f29538c_boundary-- -------------------------------1375208209--