cold weather and mpg's

[mullet man]

so i finally filled up yesterday.
i traveled 239miles on that tank of gas. i put in yesterday, 8.056 gallons to filler her up. (she was on 'E')
my average is 29.66mpg! for that tank.

i also have 155/80/13's for rubber on her.

i'm sure she could use a tune up.

does anyone know about the coolant temp sensor vs. fuel consumption thing?

[jglutz]

i also have 155/80/13's for rubber on her.

That circumference compared to a R12 with the same aspect ratio less than 5%. Thants only 1½ miles per 30 traveled....probalbly not the major contributor to your problem.

i'm sure she could use a tune up.

Always a good idea

so i finally filled up yesterday.
i put in yesterday, 8.056 gallons to filler her up. (she was on 'E')

Something is not wright the fill should have been a hair over 10 gallons...I've pushed my out of gas festiva to the pump more than once

[FB71]

all Festiva fuel gauges register slightly different. Uncle Fester (my '88) reads 'E' with just over a gallon left. My '90 reads 'E' with just under 2 gallons left.

[jglutz]

all Festiva fuel gauges register slightly different. Uncle Fester (my '88) reads 'E' with just over a gallon left. My '90 reads 'E' with just under 2 gallons left.

Lucky you...when mine reads E...it's out of gas...proved it at least 6 or more times.

[fastivaca]

9.9gal tank

really? well that certainly is going to make the MPG's worse then what i was figuring. dont know why i thought only 8gal. sitting at under a 1/4 tank now and havent even gone 200miles yet

8 imperial gallons = 10 US gallons = 38 litres

[packrat427]

http://www.net-comber.com/tirecalc.html

This says factory size vs what is on it now ..

You are going 72.026 when your speedo say 65

Revolutions per mile stock tire 981.737

Tire you have now ..885.974

Revs per second at 65 mph , stock tire .. 17.726

Your tire .. 15.997

So your are going faster than you think and you are driving more miles than your speedo is reflecting , that is why your mileage looks so low .

[jglutz]

9.9gal tank

really? well that certainly is going to make the MPG's worse then what i was figuring. dont know why i thought only 8gal. sitting at under a 1/4 tank now and havent even gone 200miles yet

8 imperial gallons = 10 US gallons = 38 litres

dude.....nothing personnal....get a new slide rule....your not even close. Rule of thumb...imperial gallons are pretty close to us gallons..not 25% dilifferent.

[mullet man]

hey Doug, does that take into account transmission gearing or final drive?

[FB71]

that's calculating the speed of the wheel, which is the same speed as the differential, which is where the speedometer gets its input. Gearing has no effect.

[Safety Guy]

Since I run 165/70-13 tires, I have to figure my mileage by adding 4.5% before dividing. My tires are essentially .5" larger diameter. I usually just do a "rough" head calculation of "half of ten percent." That usually involves around 10 miles or less per tank full.

If you don't adjust for your larger tires, you'll be off by a few tenths of an MPG--maybe up to around 1/2 MPG at most, from what I recall (especially if you round off to the nearest 1/2 MPG).

Karl

[darkdan]

My gas mileage drops to nothing in the winter. Thanks winter fuel, longer warm-ups, cold thick fluids! It goes from 36 to 38 summer to about 27 winter!