Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site ttidcc.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!godot!harvard!seismo!cmcl2!philabs!ttidca!ttidcc!hollombe From: hollombe@ttidcc.UUCP (Jerry Hollombe) Newsgroups: net.auto,net.consumers Subject: RE: Re: No Leaded Gas -- Now What? Message-ID: <263@ttidcc.UUCP> Date: Tue, 12-Mar-85 14:33:48 EST Article-I.D.: ttidcc.263 Posted: Tue Mar 12 14:33:48 1985 Date-Received: Thu, 14-Mar-85 04:53:13 EST Organization: TTI, Santa Monica, CA. Lines: 35 Xref: watmath net.auto:6076 net.consumers:1980 >From: rrh@hocsd.UUCP (r.r.hartoin) >Newsgroups: net.auto,net.consumers >Subject: Re: No Leaded Gas -- Now What? >Message-ID: <252@hocsd.UUCP> > >On this no leaded stuff. I'm in the process of rebuilding the engine >in my 69 Buick GS. One of my main objectives is to be able to run on premium >unleaded. I understand that new cars have special values which are hollow >and filled with sodium? Does this help decrease combustion chamber >temps? If so, does this aid running on unleaded. I would also like >a combustion ratio of 10:1, currently the engine has 10.25:1. >Any help on how I can rebuild this engine to burn unleaded gas >would be greatly appreciated. Thanks in advance. Sodium filled exhaust valves have been used in engines on cars and airplanes for decades and have nothing to do with gas lead content. The sodium is there to provide convective cooling of the valve head and doesn't affect combustion chamber temperature significantly. To run unleaded gas, replace your old valves and valve seats with the case- hardened type designed for unleaded. Changing the compression ratio of your cylinders means changing their physical geometry. This can be done by using a crankshaft with a different throw and/or by using different pistons. (Milling the cylinder heads will raise the compression ratio -- not what you want.) -- ============================================================================== The Polymath (Jerry Hollombe) Citicorp TTI If thy CRT offend thee, pluck 3100 Ocean Park Blvd. it out and cast it from thee. Santa Monica, California 90405 (213) 450-9111, ext. 2483 {vortex,philabs}!ttidca!ttidcc!hollombe