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Re: mileage question

To: Bob Sykes <s1500@worldnet.att.net>
Subject: Re: mileage question
From: James <james.carpenter@ukaea.org.uk>
Date: Fri, 7 Aug 1998 07:17:16 +0000
When I read that I worked it out to be 10% reduction in power is equal
to a 10% increese in economy.  I think though that was just up to
chance.  The most important thing to remember is your driving style can
change the figures +-30%.  Most people don't try two workout how much
petrol they use when there driving, but I know a chap who does.  He
worked out it costs him 2p to overtake an average car in his Ford
Excourt Cosworth.

There were a couple of propblems with the artical that I spotted, these
conclusions I made are from memory.  He jetted the single carburetter
two his tubular exhaust system, but he did not mention wether he did the
same with the dules, especialy running on 90's un-leaded.  The inlett
manifold for the 1300 was a thiner bore than the 1500, more than likely
any gain in low down power was due to that, as opposed to just one
carburetter.  The arguments for fitting single carburetters and why they
are more echonomical failed to convince me, I was proved correct when he
failed to get the estamated economy.  I would also like to see the
figures of when he drives the car using full power for the
single(4900rpm), and the equivelent of full power(single) with the
dule(4100?rpm).  To do this he would have needed to put a fule flow
meter on each test and produce a plot of fule flow per bhp (BHP v L/S). 
The fitting of any economy device makes you put your foot down less.  

Statistics can show what you wan't them to show.  I only belive my own. 

-- 
James Carpenter
Yellow '79 spit wired by a trained marmot

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