Return-Path: Received: from [24.50.193.34] (account ) by logan.com (CommuniGate Pro WebUser 4.1b2) with HTTP id 2112147 for ; Wed, 09 Apr 2003 23:58:23 -0400 From: "Marvin Kaye" Subject: Re: [LML] porting or Chuck's beautiful headers.. To: lml X-Mailer: CommuniGate Pro WebUser Interface v.4.1b2 Date: Wed, 09 Apr 2003 23:58:23 -0400 Message-ID: In-Reply-To: <000a01c2ff10$86f8b100$ebe6ea0c@attbi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Larry Graves" : We may be RPM-limited, but we aren't usually pitch-limited at full throttle. Porting/polishing, ram air induction and turbocharging/supercharging all increase horsepower because they increase manifold pressure and allow your engine (air pump) to process more airmass and fuel. When this happens at max RPM/tip speed, the prop just goes to a coarser pitch and accelerates even more air back over the plane, thrusting it forward faster. This is an overly simplistic answer -- many books have been written on the subject. Best, Larry Graves