Gas Mileage?

This may seem like a pretty dumb question, but... I have an 89 f150 regualr ole 302 in it.. Just put on some Holley headers and dual exhaust 2.25" pipes, and have 35 in tires, with 5 speed tranny... What should i be getting approximately, i know it may be hard to say, but man does my thing swallow up some gas. If i had to guess it seems like im between 7-8 mpg :/ Is this normal? Thanks.

MY OLD 1990 BRONCO HAD A 302 WITH EXAUST, 33'S, AND 3.55 GEARS, AUTO TRANNY. I GOT 11MPG IN TOWN AND 16.5MPG HWY. YOUR MPG SOUND RIGHT TO ME.

I have a 1995 F-150 w/ a 351ci and fixing to get 35's. What kind of milage am I looking at? I am also getting free flowing exhausts and a k&n air filter.

MY NEW BRONCO IS A 1996 351CI WITH 35'S, 4.88 GEARS, EXAUST & K&N FILTER, I GET 10MPG AROUND TOWN & 12MPG HWY. THE GEARS DO NOT HELP I'M AT 2'800RPM AT 65MPH.

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This may seem like a pretty dumb question, but... I have an 89 f150 regualr ole 302 in it.. Just put on some Holley headers and dual exhaust 2.25" pipes, and have 35 in tires, with 5 speed tranny... What should i be getting approximately, i know it may be hard to say, but man does my thing swallow up some gas. If i had to guess it seems like im between 7-8 mpg :/ Is this normal? Thanks.

How many miles are on the engine and what gears do you have? Is that 7-8 mpg around town or on the highway?

thank you much

The motor was rebuilt in 97 and has about 45000 Miles on it.. I am not sure of the gears, how can i find this out? I looked in the owners manuel but it gives me choices of 3.08 3.55 and 4.10.. I am assuming its 3.08 because of the fact i cannot get it rolling at all with 2nd gear? That 7-8 mpg is a mix between a short amount of highway driving and city driving, as i have yet to take it on a decent trip. But from watching the fuel gauge which i know is not a good measure on things, it seems to suck out even more gas on the short highway trips. Very discouraging seeing the mpg so bad knowing i have a 4000 mile trip coming up soon. But i guess if there is nothing i can do i will have to deal with it

Did you recalibrate your speedometer for the 35's?
If not, you're showing WAY less miles than you're actually travelling...
The speedo is reading less than you're really going.
Hence, the odometer is showing less miles...if you're using that for your calculations.
If the vehicle has never had the gears changed, look on the rear-end housing for the axle tag.
That'll have the ratio.
Let us know what the numbers say.
You didn't mention if you had an 8.8 or a 9".
(probably an 8.8 since it's an '89)
9" tag will be on the front of the housing, on one of the "pumpkin" bolts.
8.8" should have the tag on one of the cover bolts.

I havent recalibrated them, but i did figure its about every mile it records on my odometer its about 1.2 real miles. And while i'm doing 65 on my gauge its about 75-77 real mph. I tried to find any numbers i can off the rear, there was a little tag off one of the back bolts 8l55 8 8 9ed. On the front of i found some numbers E7TW 4025 BA58070.. These are the only numbers i could find. Is this any help?

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there was a little tag off one of the back bolts 8l55 8 8 9ed. On the front of i found some numbers E7TW 4025 BA58070.. These are the only numbers i could find. Is this any help?

I'll bet that's actually a "3", not an "8" on the back.
"L", would designate Limited Slip.
3L55 should be a 3.55 LSD (Limited Slip Differential).
The 8 8 denotes an 8.8" differential.
Hmmmm, the front diff should have a tag (with about the same numbers) as the rear did.
The numbers you found sound more like the axle housing part number.
I think there's a "part decoder" on this site, but I'm not sure where to find it.
Check out the following site. It may be of some help as well.
http://www.broncodata.com/

BTW, get down to your friendly Ford dealer, and pick up a new speedometer drive gear.
They may know off the top of their head which gear (number of teeth) you'd need to get the speedo back on track.
Cost should be less than $20.
That'd drive me crazy having an inaccurate indiction of speed showing.