X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 07 Jun 2011 14:18:26 -0400 Message-ID: X-Original-Return-Path: Received: from nm24-vm3.bullet.mail.ne1.yahoo.com ([98.138.91.154] verified) by logan.com (CommuniGate Pro SMTP 5.4.0) with SMTP id 5011283 for lml@lancaironline.net; Mon, 06 Jun 2011 15:41:04 -0400 Received-SPF: none receiver=logan.com; client-ip=98.138.91.154; envelope-from=mcmess1919@yahoo.com Received: from [98.138.90.54] by nm24.bullet.mail.ne1.yahoo.com with NNFMP; 06 Jun 2011 19:40:29 -0000 Received: from [98.138.84.41] by tm7.bullet.mail.ne1.yahoo.com with NNFMP; 06 Jun 2011 19:40:29 -0000 Received: from [127.0.0.1] by smtp109.mail.ne1.yahoo.com with NNFMP; 06 Jun 2011 19:40:29 -0000 X-Yahoo-Newman-Id: 130962.4583.bm@smtp109.mail.ne1.yahoo.com Received: from StevePC (mcmess1919@67.187.173.57 with login) by smtp109.mail.ne1.yahoo.com with SMTP; 06 Jun 2011 12:40:28 -0700 PDT X-Yahoo-SMTP: rK4i7HqswBC7mDE8.sOiWQeO4CeReXc- X-YMail-OSG: 7c_w90MVM1mHg3lPB3lHu.C_BqNXMyxXVbWtdNpvTidc0k9 7GD4ZmFvRUch41kth95GNziyBhGI53EEYXyDJk1bRgveqMoVPPC1nwErwSs4 tIKtQvJvtpewVYW_PMmggmXhcNtYyGl9ke.JzknBmlmWG.0YBwAKtl8R6q_f juZad.3ah07PlUZ367NHK7QqlaY67FJePU5PLez1JFg5_r3Y31bD0DxIhwrc XiH1Msh0yR3VOTjdDfBihcyqz.MITITBi4YtIfBHOCjGPgIjUrz8RTRzMaad irqkibuVnkSdgrrDJUJKriF0ySksV_pn0J8Oiot6wNZm0emTvX.qH5gWXVji lVi7zNu1zWLe3R8vOkGJ7HERQJbEfYejJISE- X-Yahoo-Newman-Property: ymail-3 From: "Steve Colwell" X-Original-To: "'Lancair Mailing List'" Subject: L-IV Choice of Engine X-Original-Date: Mon, 6 Jun 2011 12:40:27 -0700 X-Original-Message-ID: <006401cc2481$96b5f4f0$c421ded0$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0065_01CC2446.EA571CF0" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcwkgZStmRjZuLibQ8iFOXEsH2eBtw== Content-Language: en-us This is a multi-part message in MIME format. ------=_NextPart_000_0065_01CC2446.EA571CF0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit "Exhaust valve troubles won't go away because the cooling gradient between the valve and the head is so low compared to liquid cooled engines. The basic laws of physics just don't change. The constraints they impose limit solutions." The best solution to exhaust valve cooling is 2 Exhaust valves per cylinder. Heat transfers more quickly with a shorter distance to travel. Honda used a 4 valve head in the prototype aircraft engines Continental was testing for them a few years ago, most modern motorcycle engines use 2 Exhaust valves. If the economic and liability issues were solved, I'll bet we would see them in Continentals and Lycomings for better reliability and performance. Steve Colwell Legacy ------=_NextPart_000_0065_01CC2446.EA571CF0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

“Exhaust valve troubles won't go away = because the cooling gradient between the valve and the head is so low = compared to liquid cooled engines. The basic laws of physics just don't = change. The constraints they impose limit = solutions.”

The best solution to = exhaust valve cooling is 2 Exhaust valves per cylinder. Heat = transfers more quickly with a shorter distance to travel. Honda = used a 4 valve head in the prototype aircraft engines Continental was = testing for them a few years ago, most modern motorcycle engines use 2 = Exhaust valves. If the economic and liability issues were solved, = I’ll bet we would see them in Continentals and Lycomings for = better reliability and performance.

Steve Colwell = Legacy

------=_NextPart_000_0065_01CC2446.EA571CF0--