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472, how to boost fuel economy?

91K views 167 replies 26 participants last post by  cadchris 
#1 ·
Hi

I have -69 De Ville. When i bought it, car was not maintained in ages and it had very bad fuel economy, 12MPG in road drive.

Well, I replaced old airfilter and oilfilter (+oil of course) with new ones and economy went little better (13MPG).

Is there any way to lower the MPG? I have heard some people get 17 or even 18MPG fuel comsumination? With todays gas prices (1,7€/litre here in Finland, if i calculated correctly, that would mean, 8,6$/gallon:bonkers:)

Maybe I should change some ignition components such as spark plugs and breaker points. At least those looked pretty old. Are there any differences between different sparkplugs? Can I get any benefit from sparkplugs like iridium or platinum with my mechanical ignition system, or should I just buy traditional plugs like AC Delco?

I think my ignition timing is too early (something like 30-50 degrees early). Does this effect much to fuel consume?

Second thing is the carburetor. I think I'm going to do some mainteance in there too and change at least the float needle valve. I checked my cars emissions in local garage, and they were very nice, so air/gas mixtures are fine. What other things I should change there?


Are there any other things what would affect to fuel economy? I dont have EGR, Pulse air systems or any other emission control equipment.

PS. Sorry if my english was bad
 
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