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RE: Compression Ratios

To: "'Gene Eighmy'" <w4eae@netzero.net>,
Subject: RE: Compression Ratios
From: "Gene Eighmy" <w4eae@netzero.net>
Date: Wed, 26 May 2004 11:31:28 -0500
Howard just sent this clarification to me.  Sorry for my confusion:
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The 76 Spit did/does have 9.1:1 compression from the factory, as I have
one too. The owners manual states that we are to use 93/94 octane due to
high compression. The following year, 77 unleaded fuel was mandatory on
Spits and the engines were adjusted back down on compression and cat
converter was added for the new emissions standards.


To quote "The Triumph Spitfire" book by Michael Cook, page 57:
"1976: Through some technical alchemy, Triumph engineers were able to
raise Spitfire compression back to 9 to 1 for non-California cars. This
resulted in some performance benefits and in really good gas mileage -
up to 37 mpg on the highway. The catalyst-equipped California cars
continued with 7.5 to 1 compression and 33mpg. ......"

Howard





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