What kind of MPG on your Fox?

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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Dallas, GA
Although not that important, dumping all your mod money into the tank sucks. So what kind of miles per gallon, or gallons per mile are you getting with your fox?

Mine, I just don't know, it's the auto trans I think that is eating a lot of fuel as I'm only averaging about 18mpg right now. :notnice: My old fox was much more modded and I calculated about 26mpg. Didn't do too much better on the highway though. :(

Is there any mods you did to your car where you saw a MPG increase? Anything that hurt MPG's?
 
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On an AOD car, we got 17 mpg average around town with 2.73 gears.
Changed to 4.10 and it went up to 19. The car sees no highway, so no numbers there.
The mileage went up in town with 4.10s because the car doesn't have to work as hard to accel from red light to red light.
 
I get about 17 avg right now with mix driving. My old 89 got a best of 21 on the same route to work with a 306/T5-Z/4.10's. I wonder what my new engine will knock down. :eek:
 
best of 28 mpg on highway trips na with 4:10s. that was 300/300 numbers.

went to 3:55's, blower, and now at 440/410 and i have gotten a best of 26.5 so far on highway trips.

best part is i drove it all week to work, city only and i averaged 19 mpg. cannot complain...
 
What gives, why is there such a large gap here? I've done a complete tune up and feel like my car is running as efficient as a v8 car can drive, I know I stomp it frequently but I dont understand a 10 mpg difference.
 
What gives, why is there such a large gap here?

Well, 90% of the cars here have aftermarket gears, and most do not have properly calibrated speedos. By that, I mean that even with speedo recal gears, there is still error woth the shorter gears. Plus, you have non stock tires of sometimes non-oem diameter. Anything more than 3.55s on a 1990+ only has a gear that gets you "in the ballpark" on the 87-89, it's anything about 3.73. Those damn 23-tooth gears are not very accurate and off by a few MPH.

So take that into account, plus the fact that MPG is sometimes exaggerated and you get numbers all over the place.

I've seen numbers quoted in the low 30's before.....woth 4.10 gears and a supercharger. I find it funny that with such a emphasis on fuel economy these days, that 20 year old modified 5.0s get better fuel economy than a brand new technology 5.0....especially considering Fprd has a Huge CAFE goal looming ahead in the years to come. Honestly, I just don't think its possibly to accurate calculate the MPG. Hell, half the time I ride in someone elses 5.0, the speedo doesn't even work...the other times, it's pointed to 110mph at 55mph because the speedo gear was never even changed out.

I don't even trust my own mileage calculations done on my daily driver which even has a MPG computer. Never once have the numbers agreed. I usually take most claims with a grain of salt.

Just saying. :shrug:
 
i have an ssp cluster, supposively certified calibration.

i have also used gps data and speed limit signs with radar detectors to get my figures. my speedo is accurate within 1 mph of any sign/data i've had indicated.

i fill the tank, clear the odometer then divide my mileage by however many gallons til it's full again. pretty simple system, i know my mpg is accurate though. i can tell just by how the gas gauge moves on longer freeway drives.
 
Got about 27mpg on the way home from Ottawa last week. That's averaging 60mph mostly highway with a half dozen WOT passes and a couple of good romps coming out of slow traffic.

5-speed, full weight coupe, stock 2.73's, BBK CAI, Cat Back...otherwise, stock.

Not too shabby IMO. :nice:
 
i have an ssp cluster, supposively certified calibration.

i have also used gps data and speed limit signs with radar detectors to get my figures. my speedo is accurate within 1 mph of any sign/data i've had indicated.

i fill the tank, clear the odometer then divide my mileage by however many gallons til it's full again. pretty simple system, i know my mpg is accurate though. i can tell just by how the gas gauge moves on longer freeway drives.


I didn't really mean to direct my claim towards you...don't know if you thought I was referring to you since your mods were similar to the claim I saw in the past.
 
I didn't really mean to direct my claim towards you...don't know if you thought I was referring to you since your mods were similar to the claim I saw in the past.

nah, i was just stating how i calculate mine and where my claims come from :nice: ive had a fox before without the speedo gear corrected. nothing like going 60 when its really 52.. :D

there is so much crap that can play into mileage. i just keep my tires inflated, good gear oils, and (not excessively..) coast where its feasible. i just love driving my car, and getting very acceptable mileage makes it hard to drive my TL anymore.
 
Yeah I use my Garmin to calculate my mileage, I do the same I divide by how many gallons it takes to fill my tank back up. My speedometer is is slow by like 3 or 4 mph. I guess I need to count teeth on my gears to figure out if I still have 2.73's. But yeah 17 mpg looks to be the best I could get if I drive conservatively.

I just would like to know what I can do to still have plenty power and get better mpgs....
 
Yeah I use my Garmin to calculate my mileage, I do the same I divide by how many gallons it takes to fill my tank back up. My speedometer is is slow by like 3 or 4 mph. I guess I need to count teeth on my gears to figure out if I still have 2.73's. But yeah 17 mpg looks to be the best I could get if I drive conservatively.

I just would like to know what I can do to still have plenty power and get better mpgs....

you can still pull off good mileage with an efficient engine that is not working hard.. ie; cars with shorter gears dont work as much.

i think most cars would gain mileage with gear swaps once you stop putting your foot into it..
 
With the LX hatch i sold that only had an off road H and cat back i got 20 MPG average.

The notch got 15mpg on a trip that was 30% city, and the rest highway with mabye 5 1/4 mile passes on it. I dont think thats too bad considering. I expect it to go down this year with the switch from 3.73's to 4.30's