X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [161.88.255.140] (account marv@lancaironline.net) by logan.com (CommuniGate Pro WebUser 4.3.4) with HTTP id 1011157 for lml@lancaironline.net; Thu, 23 Jun 2005 09:21:45 -0400 From: "Marvin Kaye" Subject: Re: [LML] Re: Induction air filter To: lml X-Mailer: CommuniGate Pro WebUser Interface v.4.3.4 Date: Thu, 23 Jun 2005 09:21:45 -0400 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "George Braly" : Chris, What you describe is certainly consistent with the traditional notion of detonation damage. Did you have a six probe EGT/CHT instrument? Did you notice that the CHT went up? Light to moderate detonation, in the absence of allowing the CHTs to rise significantly, usually doesn't do much harm. When the CHTs rise or it gets to be heavy detonation for prolonged periods, then that can do the kinds of things you describe. However, what often or even usually happens is that problem turns into pre-ignition and that destroys an engine rather rapidly. Part of the problem in this whole area is that the distinction and definitions between light, medium, & heavy detonation are not well identified. Regards, George > A few year back my plane was topped off with 20 gallons of fuel that was > about 95% avgas and 5% Jet A.