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Hey everybody! I have a question about mpg. My '67 coupe has a 289 that has been bored over .030 by a PO. The carb is an older Holley 4160 series that has been rebuilt. My fuel pump is new, and is made for a 4 bbl carb, which I have. My plugs and wires are in great shape, I have a Pertronix ignitor and 40,000 volt coil, and I run an 11" K&N open filter. My car burns a lot of oil, and puts out light gray smoke most of the time that it is running (maybe a mixture of oil blow-by and incompletely burnt fuel?). My question, finally (!), is this, what can I do to increase my mpg? My car is a daily driver (I can't stand to drive anything else) and gets about 10 mpg in city driving, and 12-13 mpg on the highway. I use 87 octane gas. Is this about as good as I can expect, or can some adjustments be made that will help increase the mpg? Thanks for your help!
 

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If youre getting that much with continuous smoke out the tailpipes, consider yourself lucky!!!!

continuous light gray smoke probably means your rings are worn (UNLESS the car sat for MANY years, which in isolated cases could be stuck rings....it's VERY rare)

I'm assuming the plugs get nasty quickly........changing them stupidly frequent MIGHT make a difference
 
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