The newest Subaru engine that they are using is an aircraft engine, it was designed for this purpose the plane just did not take off. They then put it in a car.
Dan ----- Original Message ----- From: "Scott William" <scot...@yahoo.com> To: <brokerpilot9...@earthlink.net>; "KRnet" <kr...@mylist.net> Sent: Monday, October 17, 2005 6:23 AM Subject: Re: KR> Eggenfellner engines > Can I simplify this? > > Auto engines are engineered to spend 80% of thier life > at 20% throttle. > > > Airplane engines are engineered to spend 80% of thier > life at 85% throttle. > > > See the difference? > > Now, some auto engines have inherent design > charachteristics that bode them well in airplanes. The > Corvair is one that is superb. As mentioned below, the > 2100 VW with a good forged steel crank is a good > choice, as is the V6 GM motor. > > As for all the others.....look how they perform in > boats. They don't last long because of the large power > requirements on them. Hence, you'll never see a two > bolt main Chevy 350 in a boat. Or a Subaru, for that > matter. > > > Scott > > --- Colin Rainey <brokerpilot9...@earthlink.net> > wrote: > >> Bob Lester at one time ran a Subaru engine before >> changing over to a Corvair. Problems with the >> crankshafts due to the high rpms necessary to >> produce enough power. Read the Auto Mathbook for >> some numbers of projected life expectancy when >> engines are subjected to higher and higher rpms. >> The Chevy 350 is 3.48 inches in stroke and will >> reach a piston speed that at 6500 rpms will stress >> the crank 4 times what it is at 5500 rpms per the >> author of the book. Yet by de-stroking that same >> engine as in the Indy cars, it can be revved to >> 11,500 and reach the same piston speeds as 6000 >> rpms, bringing the same stress to the crank. You >> must do the same things to your chosen engine, OR >> use an engine that develops more HP than you need, >> so that your rpms can be maintained at a reasonable >> level for longevity. The chosen engine needs to >> have a broad power band where torque is good where >> you plan to cruise. Peak Hp does not matter if you >> cannot stay there for long durations. Remember about >> takeoffs, climbs while in cruise flight. etc... >> >> With the complexity with running a liquid cooled >> auto engine added to an already complex task of >> setting up an engine and then matching a prop to it, >> the idea of getting reliable information concerning >> PSRUs and prop matches is nothing short of daunting. >> The Subarus are reputed to produce X amount of HP >> but I was not impressed with their presentation nor >> information, or lack there of at Sun n Fun, from the >> Eggenfellner group. They seemed full of hipe but >> would not talk real world knowledge of their >> products. Like REAL hours of use instead of >> projected TBO. Their full rated HP falls WAY off >> when throttled back for economy cruise. For all the >> added extras in complexity and weight, you are >> better off with a good 2180 VW or Corvair 2.7L. The >> three best auto engines I have researched that are >> successful conversions, being used extensively, with >> LOTS of information available are: 1) the VW 2180; >> 2) the Corvair 2.7L ; 3) the 4.3V6 GM. By far these >> engines have way over the numbers of flying >> conversions that stay in the planes and the owners >> express satisfaction with their performance. The >> others have smaller numbers, and have short TBOs >> like the 2 cycle Rotax family. >> >> IMHO I would recommend for our birds, stick with the >> proven power plants and you will fly sooner, be >> happier, spend less money, and perform better than >> these other fancy boat anchors. (Ok maybe not boat >> anchor, but definitely tie down anchors ). >> >> >> Colin Rainey >> brokerpilot9...@earthlink.net >> EarthLink Revolves Around You. >> _______________________________________ >> Search the KRnet Archives at >> http://www.maddyhome.com/krsrch/index.jsp >> to UNsubscribe from KRnet, send a message to >> krnet-le...@mylist.net >> please see other KRnet info at >> http://www.krnet.org/info.html >> > > > > > > __________________________________ > Yahoo! Mail - PC Magazine Editors' Choice 2005 > http://mail.yahoo.com > > _______________________________________ > Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp > to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net > please see other KRnet info at http://www.krnet.org/info.html > > > > -- > No virus found in this incoming message. > Checked by AVG Anti-Virus. > Version: 7.0.344 / Virus Database: 267.11.14/129 - Release Date: > 10/11/2005 > >
