X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [68.202.132.19] (account marv@lancaironline.net) by logan.com (CommuniGate Pro WEBUSER 5.1c.4) with HTTP id 1409174 for lml@lancaironline.net; Mon, 18 Sep 2006 21:04:45 -0400 From: "Marvin Kaye" Subject: Re: [LML] Backfires LOP To: lml X-Mailer: CommuniGate Pro WebUser v5.1c.4 Date: Mon, 18 Sep 2006 21:04:45 -0400 Message-ID: In-Reply-To: <007801c6dae2$df9efb00$8980a8c0@nvidia.com> References: <007801c6dae2$df9efb00$8980a8c0@nvidia.com> X-Priority: 3 MIME-Version: 1.0 Content-Type: text/plain;charset="iso-8859-1";format="flowed" Content-Transfer-Encoding: 8bit Posted for "colyncase on earthlink" : Jim said, If anyone wants my opinion it is that the exhaust valves on the TSIO-550E can not cool themselves enough while LOP even when power is back to 28/2400 because it is still at 1550F EGT and that makes the exhaust valve so hot that the valve seat has to be wide and perfect to take all the heat ouf of the valve head, or the heat goes up the stem and burns the oil off the stem therefore wearing the stem and guide very fast. Jim, I'm not following your logic here. Why couldn't you lower egt by going leaner? What EGT are you getting ROP? Will a valve seat that isn't perfect run okay at that temp? Seems like you have to have great valves at any temp on this engine. Colyn