Return-Path: Received: from pop3.olsusa.com ([63.150.212.2] verified) by logan.com (CommuniGate Pro SMTP 3.5.1) with ESMTP id 999639 for rob@logan.com; Sat, 29 Dec 2001 11:51:59 -0500 Received: from smtp004pub.verizon.net ([206.46.170.183]) by pop3.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-71866U8000L800S0V35) with ESMTP id com for ; Sat, 29 Dec 2001 10:51:57 -0500 Received: from GCasey (calnet31-66.gtecablemodem.com [207.175.254.66]) by smtp004pub.verizon.net with SMTP for ; id fBTFqqJ14518 Sat, 29 Dec 2001 09:52:52 -0600 (CST) Reply-To: Reply-To: lancair.list@olsusa.com From: "Gary Casey" To: Subject: auto vs. aircraft engines Date: Sat, 29 Dec 2001 07:51:09 -0800 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit In-Reply-To: <20011223051446.AAA28668@pop3.olsusa.com> Importance: Normal X-Mailing-List: lancair.list@olsusa.com <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> >>The comments, contributions, and corrections of others are always welcome. Fred Moreno<< Excellent reply, Fred. Your are right in that the real BSFC of an aircraft engine is unknown because the pilot is the "engine designer" - he can run the engine any way he wants and suffer/enjoy the consequences. We stopped doing that in cars maybe 75 years ago. Only one question left - you mention the potential for a BSFC of 0.4 lb/hp-hr and that seems to be below any I have seen in real life. Automotive engine testing done at GM (I have pretty old data, though) shows a minimum of about .42 - .44 for high compression 10:1 engines and .44 to .48 for low-compression 8.5:1 engines. Granted, this is only 10% different, but that is still a pretty big gap. With a modern low-friction engine and better air/fuel distribution maybe the .40 is possible. I am hoping that my V-8 with a compression ratio of about 9.5 can beat the BSFC an 8.5 aircraft engine by 2 - 4%. Is there a difference in heating value for aircraft fuel compared to car gas? Don't know. Gary Casey >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://members.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please remember that purchases from the Builders' Bookstore assist with the management of the LML. Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>