150 miles and my gas is gone

1991vert

10 Year Member

Feb 27, 2004

1,103

7

69

Ludlow, MA

Jul 23, 2005

#1

• Jul 23, 2005

• #1

so what seems to be my problem? i usually shift at 2k rpm.

a fox tank can carry what, 14 gallons? so 150miles/14gallons is a little less than 11mpg. quite pathetic with a n/a 302.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

34

129

Jul 23, 2005

#2

• Jul 23, 2005

• #2

I would fill up and calculate exact milage. Any codes? Bad lambdas will really cut down milage, as can running too cool (not getting into full fuel trim).

Good luck.

 

Foxfan88

My Grandpa has great wood.

Sep 13, 2004

2,487

4

0

Miami, Ok

Jul 23, 2005

#3

• Jul 23, 2005

• #3

Fox tanks are 15.4

My car get **** milage too, i avergae about 12 mpg mixed, more city driving than highways though.

 

maverick0716

Founding Member

Jan 12, 2002

3,924

0

56

Chilliwack, BC, Canada

Jul 23, 2005

#4

• Jul 23, 2005

• #4

My stang gets pretty bad mileage too....but that's do the A) Carburetor B) My work is about 2-3 kms away, so it doesn't even heat up before I'm there.

 

dkins419

New Member

Nov 14, 2004

187

0

0

Michigan

Jul 23, 2005

#5

• Jul 23, 2005

• #5

I have the same problem. I already have done 02 sensors, plugs/wires, air filter, cap/rotor, sea foamed it, and it runs great. but i did gaina bout 2 mpg after but still.....

 

1

1990LXDropTop

New Member

Dec 4, 2003

430

0

0

Western Massachusetts

Jul 23, 2005

#6

• Jul 23, 2005

• #6

I just gased up my nearly empty tank today. I reset the odo everytime I gas up so I know what kind of mileage I'm getting. Today it read 166, which was with no highway driving all week. Last year I drove my car 5 hours on the highway to NY and only used a half tank of gas. On that tank I think I got 250+ miles. You get much better mileage on the highway than around town in these cars....

 

S

Scorcher2005

Member

Apr 17, 2004

883

0

16

South Carolina

Jul 23, 2005

#7

• Jul 23, 2005

• #7

that sucks...i get about 140-160 miles out of 10gallons or so. Check and clean these things: http://www.muscularmustangs.com/iac.php

 

Nutzy19

Member

Mar 30, 2005

120

0

16

Flemington NJ

Jul 23, 2005

#8

• Jul 23, 2005

• #8

Foxfan88 said:

Fox tanks are 15.4

My car get **** milage too, i avergae about 12 mpg mixed, more city driving than highways though.

Click to expand...

Try more like 13.5-13.8.....

 

1

1990LXDropTop

New Member

Dec 4, 2003

430

0

0

Western Massachusetts

Jul 23, 2005

#9

• Jul 23, 2005

• #9

Nutzy19 said:

Try more like 13.5-13.8.....

Click to expand...

No, they are more than 13.8. I just dumped 14.115 gallons or something like that in my tank today.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

34

129

Jul 23, 2005

#10

• Jul 23, 2005

• #10

No, I think Fox Fan is right about the tank capacity.

 

R

Retro10

New Member

Jun 7, 2005

42

0

0

Jul 23, 2005

#11

• Jul 23, 2005

• #11

I get really bad gas mileage as well in the city...not sure why I have such a huge difference but I get around 11 in the city but 26 mpg highway..

ETA: I have a 93 GT

 

S

Scorcher2005

Member

Apr 17, 2004

883

0

16

South Carolina

Jul 24, 2005

#12

• Jul 24, 2005

• #12

if i recall from my 91 owner's manual, it said tank capacity is 15.9 gallons

 

Grn92LX

Fidanza Man!

Founding Member

Jan 14, 2001

6,819

64

129

New York

Jul 24, 2005

#13

• Jul 24, 2005

• #13

It is a 15.x gallon tank. I just put in almost 13 gallons today and my gauge was on 1/4 tank.

I am getting junk mileage as well, but I have a fresh 347 that I been tuning and having some fun with I almost got 10mpg this tank. I figure with normal driving it should improve. It should get at least 15 or so around town i'm hoping.

My idle and cruise a/f are ideal according to my wideband.

 

stang8urimport

Autozone Junkie

Founding Member

Jun 21, 2002

1,499

12

59

Daytona Beach, FL

Jul 24, 2005

#14

• Jul 24, 2005

• #14

Last fill up, I got 220 Mile to the tank.. on like 14.5 gallons.... Like 16 MPG... but I also lug it around in 5th gear all the time. that's the KEY. If I just leave it in 4th, and cruise around, I'll get 160-170 miles to a tank... 5th gear is your friend, folks.

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

79

Charlotte, NC

Jul 24, 2005

#15

• Jul 24, 2005

• #15

Doesn't matter what the tank capacity is -- use the reading off the station pump to determine how much you've used. And you have to be sure your odo is reasonably accurate - changing tire size and/or rear gears without correcting the speedo can really throw the odometer reading off which wreaks havoc with fuel mileage calcs. You can't do a reasonable estimate of mileage by looking at the fuel gauge and estimating fuel use (e.g. - 3/4 of a tank on the gauge means I used about 11 gallons) -- there's WAY too much variation on the gauges.

The biggest variable is driving style and conditions. It's pretty difficult for these engines in 3000-3500 lb. cars to do any better than about 14-15 mpg in heavy stop and go conditions. With a modded car that makes more HP at high rpm, and less torque at low rpm, it can be even worse as the engine spends most of it's time on the street in an rpm range that isn't very efficient for the modded motors. I live in a relatively small town, so my 'city' mileage isn't really impacted by heavy stop and go. With a mild H/C/I combo, and 3.73 gears (with slightly shorter tires than a STang - think 3.90 gears in a Stang) mine consistently gets 19-20 mpg around town, and 25-27 mpg on the highway. That's driven VERY conservatively -- I spend as little time above 2500 rpm as I have to. I'm turning over around 2300 rpm at 65 mph.

 

1988WHTGT

Member

Mar 31, 2005

270

0

17

Guyton, GA

Jul 24, 2005

#16

• Jul 24, 2005

• #16

What kind of SeaFoam stuff does everyone use? Just the stuff for the fuel or what?

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

79

Charlotte, NC

Jul 24, 2005

#17

• Jul 24, 2005

• #17

1991Vert - with a heavier vert, and that 2040 (E) cam, part of the problem is that you probably have much less torque between idle and 2500 rpm than you did before -- that lack of torque in a heavier car is gonna KILL around town mileage. When you rebuild with boost I'd strongly consider going with a cam choice that returns some bottom end; and a positive displacement supercharger (KB for example) will return more bottom end than a centrifugal (Vortex for example) will in the heavy vert.

 

1991vert

10 Year Member

Feb 27, 2004

1,103

7

69

Ludlow, MA

Jul 24, 2005

#18

• Jul 24, 2005

• #18

michael, cam will be custom ground and im not too keen on the idea of the kenne bell because it's a torque MONSTER and driveability would suffer.

so i guess my mpg is normal? i dont do any highway driving with the car. dont want to get it dirty with bugs

 

Michael Yount

Mustang Master

Apr 10, 2002

9,039

6

79

Charlotte, NC

Jul 24, 2005

#19

• Jul 24, 2005

• #19

"because it's a torque MONSTER and driveability would suffer."

You and I must define 'drivability' differently. Lots of torque down low is what makes one, especially a heavy vert, FUN to drive -- it ENHANCES drivability. That's why I suggested it. But apparently you have other ideas. Good luck with it.

 

86T-Top

Founding Member

Jun 29, 2001

553

0

17

Dublin, PA

Jul 24, 2005

#20

• Jul 24, 2005

• #20

So did these foxes have different size gas tanks? My manual says I have a 15.xx gallon tank, but I have never stuffed more than 13.xx gallons in the car, even when I almost ran her out of gas.

Mario