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  • Fox 5.0 Mustang Tech

How to save gas in a 5.0

  • Thread starter Thread starter fivespeedstang
  • Start date Start date Sep 17, 2007
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ninety15.0

New Member
Mar 10, 2004
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Sep 18, 2007
#21
  • Sep 18, 2007
  • #21
Thats great bro...but honestly i don't care about what your bike gets for mileage and im sure the original poster doesn't either. Im sure if he had the means to buy an econo car, he would have. But for the time being he asked for tips to increase the fuel economy of the car he currently owns. This is a tech forum. Telling this guy that he shouldnt be driving a stang b/c he cares about fuel economy is ludicrous. There's nothing wrong with having your cake (fast stang) and eating it too (good fuel economy)....in fact i think thats even better. I love telling people i knock down 25+ every time i get on the highway...with my almost 20 year old American "sports car."
 
I

iwashmycar

20+ Year Stangneter
Apr 7, 2004
1,236
1
39
Columbus, Ohio
Sep 18, 2007
#22
  • Sep 18, 2007
  • #22
i just keep it under 2-2500 usually. I get about 300/tank
 

hungrymonkey

White by Birth, Trash By Choice
Founding Member
Nov 29, 1999
3,077
12
108
Oregon.
Sep 18, 2007
#23
  • Sep 18, 2007
  • #23
proper tire inflation adds a signifigant percentage to your MPG.

Plus whatever everyone else said about keeping it maintained.


My .02

I am with SVT on this one. I only drive 3 miles to work. But I always have a poo eating grin on my face when I get there

I used to drive an accord, filled it once a month when I hit the 300 mile mark on the tank. But it was not nearly as enjoyable of a drive.

30, married for 10 years, 3 kids.

I guess its stress relief. between the screaming babies, both at home and at work, and whatever my wife feels the need to complain to me about. Its the most enjoyable "me time" that I have.
 

Flavadave4

Active Member
Nov 28, 2003
1,044
21
49
Utica, NY
Sep 18, 2007
#24
  • Sep 18, 2007
  • #24
ttop88 said:
Could every one that responds to this please put your age and marital status. I would love to see how this pattern looks. I have gotten as much as 30mpg with a 89 gt. 3.55 gears good tune and driving style will take you a long way.
31 single
Click to expand...



25, been married for a year.

I have a sweet pick up that i daily drive, gets about 14-17mpg. So when I drive the car its for fun or something different so why not give 'er hell? Its not like I red line every shift, but If i want to stomp on it I do, why you ask.......because it puts a smile on my face and thats why I bought and love my car.
 

samickguy15

Member
Sep 1, 2005
404
0
16
Delavan, IL
Sep 18, 2007
#25
  • Sep 18, 2007
  • #25
.

I think the technical points contributed here are good. Not non-technical should really remain unsaid.

I personally am concerned about mileage as I drive 50 miles each way to work. I bought a Mustang because that's what I liked. My 2.3 gets about 26 with 75-80 on the interstate and some heavy pedaling through the country before home. I will do what I can to get the 5.0 to do the same when it gets on the road.

Oh...22 and probably married in the near future...Maybe age and gross income would be better, not marital status...
 

strtrcr50

New Member
Jun 21, 2006
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4
0
Previously from Dirty Jerzey exit 7a
Sep 18, 2007
#26
  • Sep 18, 2007
  • #26
34, engaged
I have no idea what kind of mileage my fox gets because I very rarely drive it. Here's an interesting read about mixing acetone with your gas to increase mileage. link Here's some guys who are testing it out. link
 
P

patrickmx2

New Member
Jul 25, 2007
32
0
0
Near Memphis TN
Sep 18, 2007
#27
  • Sep 18, 2007
  • #27
Yes. I own two Mustangs. I have done extensive tuning and data logging with my Tweecer R/T. I can provide logs to those that disbelieve. I tune both with an LC-1 wide band to confirm my AFR. I run one 17:1 typically and use ACETONE for octane increase because I run 87 in both cars. On the eectuning board me and another are testing combinations for this.


Let me break it down this way. I'm sure this could have potential to start a flame war, but again I can provide data as proof in real time data logging and also at the pump.

1989 Fox Coupe. Daily driver. OEM 97 Explorer engine. 10" TCI converter, AOD, 3.27 gears. Mac Pro chamber and FACTORY mufflers. Car weighs 3500lb with driver. Fully loaded and 100% restored with extra sound deadening for 100 mile daily commutes.I have logged as high as 31 mpg at 55-65. 4 lane driving at 75-85 27-28mpg. 17:5-18:1 AFR... (Open Loop cruise) I have since richened it back up due to the plug reading is too lean and I don't want exhaust valve problems. 87 Acetone seems to have helped by about 2mpg. The base factory A9P EEC tune gave me 21-26mpg and no more.


1990 Fox Coupe. This is a near identical car but with an E303 cam, 1.7 roller rockers, Edelbrock RPMII, Edelbrock exhaust mufflers, same headers and Mac ProChamber. 4.10 gears and an AODE (the car is wired 94-95 spec CBAZA EEC to control the tranny.

16mpg base max with factory tune. With 400 miles of tuning and logging I'm now up to 20mpg. The 4.10 gears are coming out next week for some 3.31's. This car hasnt gotten the acetone treatment yet. I'm still in closed loop and running stock AFR on this car. For more research on Acetone go here:

http://peswiki.com/index.php/Directory:Acetone_as_a_Fuel_Additive

School is divided on benefits. So just try it and judge for yourself.

also go here for some of our own testing: (join in if you would like)

http://eectuning.org/forums/viewtopic.php?t=8156&postdays=0&postorder=asc&start=0


My 1989 coupe runs mid 13's. (8.60's on 1/8th mile)
My 1990 coupe is stronger but I haven't run it yet.

The cars can be seen here: http://s154.photobucket.com/albums/s247/patrickmx2/
 

chr1s11575stang

New Member
Aug 16, 2007
64
0
0
Orlando, Fl
Sep 18, 2007
#28
  • Sep 18, 2007
  • #28
I drive mine like a bat outta hell and i still get like 13-15 mpg. I get like 242 per tank this week but next week it will be 180. I figure who cares thats what its for. The wrath of Chris.


.........Oh yeah 32 divorced 2 kids...and the kids enjoy the speed too. Thats actually when I use more cuz they are egging me on.
 

Flavadave4

Active Member
Nov 28, 2003
1,044
21
49
Utica, NY
Sep 18, 2007
#29
  • Sep 18, 2007
  • #29
patrickmx2 said:
Yes. I own two Mustangs. I have done extensive tuning and data logging with my Tweecer R/T. I can provide logs to those that disbelieve. I tune both with an LC-1 wide band to confirm my AFR. I run one 17:1 typically and use ACETONE for octane increase because I run 87 in both cars. On the eectuning board me and another are testing combinations for this.


Let me break it down this way. I'm sure this could have potential to start a flame war, but again I can provide data as proof in real time data logging and also at the pump.

1989 Fox Coupe. Daily driver. OEM 97 Explorer engine. 10" TCI converter, AOD, 3.27 gears. Mac Pro chamber and FACTORY mufflers. Car weighs 3500lb with driver. Fully loaded and 100% restored with extra sound deadening for 100 mile daily commutes.I have logged as high as 31 mpg at 55-65. 4 lane driving at 75-85 27-28mpg. 17:5-18:1 AFR... (Open Loop cruise) I have since richened it back up due to the plug reading is too lean and I don't want exhaust valve problems. 87 Acetone seems to have helped by about 2mpg. The base factory A9P EEC tune gave me 21-26mpg and no more.


1990 Fox Coupe. This is a near identical car but with an E303 cam, 1.7 roller rockers, Edelbrock RPMII, Edelbrock exhaust mufflers, same headers and Mac ProChamber. 4.10 gears and an AODE (the car is wired 94-95 spec CBAZA EEC to control the tranny.

16mpg base max with factory tune. With 400 miles of tuning and logging I'm now up to 20mpg. The 4.10 gears are coming out next week for some 3.31's. This car hasnt gotten the acetone treatment yet. I'm still in closed loop and running stock AFR on this car. For more research on Acetone go here:

http://peswiki.com/index.php/Directory:Acetone_as_a_Fuel_Additive

School is divided on benefits. So just try it and judge for yourself.

also go here for some of our own testing: (join in if you would like)

http://eectuning.org/forums/viewtopic.php?t=8156&postdays=0&postorder=asc&start=0


My 1989 coupe runs mid 13's. (8.60's on 1/8th mile)
My 1990 coupe is stronger but I haven't run it yet.

The cars can be seen here: http://s154.photobucket.com/albums/s247/patrickmx2/
Click to expand...

Very interesting
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Sep 18, 2007
#30
  • Sep 18, 2007
  • #30
ninety15.0 said:
I really dont agree with you at all on this matter. Whats wrong with knocking down good gas mileage on your daily driven fox? Sure if you have a econo car for daily driving then you're lucky and you shouldnt be contributing to this conversation. I daily drive my 300+ HP mustang and knock down good gas mileage. I always get 25+ on the highway doing 75-80mph...and driving back and forth to work i always get 18-19. Its all about matching the right parts and knowing how to drive a car like this.

Here's a couple tricks i have learned. mechanically...everything must be in perfect working order. Good plugs (properly gapped), cap, rotor, wires, and fuel filter. Timing...on a fox i think 12° will net you the best balance between performance and economy. You can always take 3 minutes to bump it up at the track or cruise night! Obviously weight and tire pressure are important. Also look into good synthetic oils/lubricants. Running a good gear oil and tranny fluid will go a long way in reducing fiction. Not to mention good motor oils reduce friction and run cooler...all these things will marginally boost efficiency.

Gear ratio: Honestly the stock 2.73 are horrible for economy. They are simply too long. 3.27 and 3.55 are the best ratios for getting good mileage...and which of those you choose depends on the conditions you drive in. All highway -- 3.27. Mixed driving -- 3.55. Gears give you higher torque multiplication...and that effective increase in torque gets the vehicle moving easier (less throttle input) and gets you into high gear sooner. Both my brother and i got better mixed driving mileage after swapping to 3.55's and 3.73's from the stockers. Our highway mileage has remained exactly the same.

Driving style: Get a vacuum gauge and watch it like a hawk. Manifold Vacuum is directly proportional to the efficiency of a motor. The less throttle input required to maintain a desired speed..obviously the better. An engine is simply an air pump...when you let more air in...you let more fuel in. Also...do not listen to people who tell you to shift really early ~below 2000. While this is good advice some of the time it is not entirely true. Buy a Vac gauge and shift real early and you will see what i mean. The motor loads up really bad when you accelerate in the lower rpms. I bring 1st and 2nd up to at least 2500 every time and b/c you arent pressing the gas hardly at all...vacuum is high and you arent using very much gas. And when you upshift you dont land really low in the rpms...so the subsequent gears require less throttle input to accelerate as well.

You can wring out quite a bit of economy from these cars if you are willing to keep your foot out of it.
Click to expand...

I like it!

I had thought (back in the day) to buy a little Honda or something for gas for a few thousand. Then I thought how that would be no fun, and I could USE the few thousand on gas money, and keep one insurance payment
 
R

Rdrcr

Member
Jul 7, 2007
77
1
9
Thousand Oaks, CA.
Sep 18, 2007
#31
  • Sep 18, 2007
  • #31
Patrickmx2, very interesting and informative. Do you feel that the acetone is better than using regular 91/93 octane?

With my '86 5-spd. 2.73 I'm averaging 22 mpg city/hwy on 91 octane including the use of A/C. I just recently switched from 87 octane to 91 due to a more aggressive timing change.

Mike
 
P

patrickmx2

New Member
Jul 25, 2007
32
0
0
Near Memphis TN
Sep 18, 2007
#32
  • Sep 18, 2007
  • #32
Rdrcr said:
Patrickmx2, very interesting and informative. Do you feel that the acetone is better than using regular 91/93 octane?

With my '86 5-spd. 2.73 I'm averaging 22 mpg city/hwy on 91 octane including the use of A/C. I just recently switched from 87 octane to 91 due to a more aggressive timing change.

Mike
Click to expand...

better = cheaper. 2 ounces of acetone per 10 gallons of gas to get 3 points in octane increase is cheaper than the difference between 87 and 90 octane gas alone.

I did extensive tuning on my 1989 Mustang prior to running any Acetone to get the maximum MPG through tuning alone. This involved the creation of many 4mb commute log files per 50 mile leg of my daily drive. Once I began using the acetone I noted my KAM's started generating and my AFR varied by 2 points on the wide band (all of this is explained on my eectuning link above).

So I had to redial in my AFR for the acetone to get the car leaned back out. As you probably know octane slows down the burn process. Hence it also increases the flashpoint of the fuel. The flashpoint is the temperature at ignition. To keep the fuel from PRE-ignition you have to add octane to raise the flashpoint. The fire tetrahedron consists of three things. Oxygen, fuel, and a heat source. So Octane takes care of the heat source usually due to compression or a hot summer day. Once you raise the flashpoint (slow down the burn process and tendancy to pre-ignite) you can then rely solely on the spark plugs for the heat source.


In summary of your question, if you read up on Acetone and the mixture, you can see that Acetone has an effective octane rating of 150. The research indicates 2 to 3 ounces of acetone per 10 gallons of gas. Acetone also changes the surface tension of the fuel.

Oh, and to avoid the questions about plastics and the fuel system. I am going to upload a picture of my 1quart acetone container (bought from a hardware store) that has a plastic cap on the metal container. Automotive grade plastics resist acetone.

I use a stainless steel funnel and a small shot glass sized measuring cup. I also line and protect the side of my car with a shop towel just as a precaution.

As a US Air Force Fuels Specialist I also use proper grounding procedures while adding the acetone. - Our local media recently did a test to determine the statistics on gas station accidents due to sparks at the time of fueling. The results were younger women during the winter time were the majority. Why? Because they tend to get in and out of the car due to the cold, wearing some sort of coat or on the phone, which takes their free hand they might use to close the door with and they use an elbow or something. The phone wasn't the cause in any case.

Coincidentally elderly people hardly made the statistic either way. Because they use the door for assistance to get out of the car, thus grounding themselves when they get out of the car, even if they get back in due to the cold.
 

BK_CAULEY

it's built for speed not longevity, woman
Dec 26, 2006
0
10
49
Thomasville, ga
Sep 18, 2007
#33
  • Sep 18, 2007
  • #33
put sugar in your gas tank.






































dont really put sugar in there. dont think you are that dumb but never know.
 
P

praugue

New Member
Sep 18, 2007
26
0
0
Sep 18, 2007
#34
  • Sep 18, 2007
  • #34
Keep the gas tank at 1/4. It's a lot less weight.
 
R

Rick Johnson

New Member
May 22, 2007
1
0
0
Feb 11, 2008
#35
  • Feb 11, 2008
  • #35
How did you get to 20 MPG from 16?

patrickmx2 said:
Yes. I own two Mustangs. I have done extensive tuning and data logging with my Tweecer R/T. I can provide logs to those that disbelieve. I tune both with an LC-1 wide band to confirm my AFR. I run one 17:1 typically and use ACETONE for octane increase because I run 87 in both cars. On the eectuning board me and another are testing combinations for this.



1990 Fox Coupe. This is a near identical car but with an E303 cam, 1.7 roller rockers, Edelbrock RPMII, Edelbrock exhaust mufflers, same headers and Mac ProChamber. 4.10 gears and an AODE (the car is wired 94-95 spec CBAZA EEC to control the tranny.

16mpg base max with factory tune. With 400 miles of tuning and logging I'm now up to 20mpg. The 4.10 gears are coming out next week for some 3.31's. This car hasnt gotten the acetone treatment yet. I'm still in closed loop and running stock AFR on this car.

My 1989 coupe runs mid 13's. (8.60's on 1/8th mile)
My 1990 coupe is stronger but I haven't run it yet.

The cars can be seen here: http://s154.photobucket.com/albums/s247/patrickmx2/
Click to expand...

(My 1991 5.0 vert with 15 BTDC degrees timing and the throttle position sensor set to minimum voltage at idle seems like a gas hog at 15MPG) You mentioned you are still running in closed loop on the 1990 and getting 20 MPG. What changes did you make to improve your mileage and still use the factory closed loop control?

Thanks,
Rick
 
P

patrickmx2

New Member
Jul 25, 2007
32
0
0
Near Memphis TN
Feb 11, 2008
#36
  • Feb 11, 2008
  • #36
Rick Johnson said:
(My 1991 5.0 vert with 15 BTDC degrees timing and the throttle position sensor set to minimum voltage at idle seems like a gas hog at 15MPG) You mentioned you are still running in closed loop on the 1990 and getting 20 MPG. What changes did you make to improve your mileage and still use the factory closed loop control?

Thanks,
Rick
Click to expand...

First let me say I have gone beyond 20 and have datalogged as high as 28 at very light loads on a 35 mile trip running 70mph. BUT did so in Open Loop and I adjusted the Fuel - Open Loop Stabilised table (FN1360)

My values verses the stock values further down. Notice my values are much leaner in the low loads. Now closed loop is below that.

17.04 17.04 14.30 13.73 12.12 12.12 12.12 12.01 12.12 12.35
17.04 17.04 14.30 13.73 12.12 12.12 12.12 12.01 12.12 12.35
17.04 17.04 14.75 13.95 13.95 13.73 13.73 13.04 12.12 12.35
14.75 14.75 14.30 14.18 14.18 14.18 14.18 14.18 12.12 12.35
14.75 14.30 14.18 14.18 14.18 14.87 14.87 14.53 14.30 14.30
14.18 14.18 13.61 13.61 14.98 15.44 15.21 14.98 14.98 14.98
13.50 13.50 13.95 13.95 14.98 15.44 15.44 17.04 17.04 17.04
15.21 15.21 15.21 15.21 16.01 17.04 17.04 17.04 17.04 17.04


12.35 12.35 12.47 12.12 12.12 12.12 12.12 12.01 12.12 12.35
12.35 12.35 12.47 12.12 12.12 12.12 12.12 12.01 12.12 12.35
14.30 14.30 14.30 14.30 14.30 14.30 12.12 12.01 12.12 12.35
14.30 14.30 14.30 14.30 14.30 14.30 12.12 12.01 12.12 12.35
14.30 14.30 14.30 14.30 14.30 14.30 14.30 14.30 14.30 14.30
14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18
14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18 14.18
13.95 13.95 13.95 13.95 13.95 13.95 13.95 13.95 13.95 13.95

As far as CLOSED LOOP what I did was adjust HEGO Amplitude and BIAS

Amplitude FN1352. My values verses stock below.
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313
0.0313 0.0313 0.0313 0.0313

0.0801 0.0605 0.0547 0.0508
0.0801 0.0605 0.0547 0.0508
0.0801 0.0605 0.0547 0.0508
0.0801 0.0605 0.0547 0.0508
0.0801 0.0605 0.0547 0.0508
0.0605 0.0703 0.0547 0.0508
0.0605 0.0801 0.0352 0.0352
0.0605 0.0801 0.0352 0.0352

HEGO BIAS. FN1353 My values verses Stock below that.

0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.1992 0.1992
0.0000 0.0000 0.1992 0.1992
-0.1504 -0.1504 0.2480 0.2480
-0.1504 -0.1504 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000

0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000

For more detailed information and research go to www.eectuning.org and do a search for MPG, HEGO Bias and other terms. It will help you get knowledge about the process.

Now as far as your TPS sensor voltage. I don't see how that will ever impact your MPG. If you had a way to trim the signal on the MAF maybe but that would effect so many things.

This entire post assumes you have a Tweecer R/T and a good Wideband O2 to confirm your AFR feedback.
 

NKau

Founding Member
Dec 15, 2001
1,346
0
37
Jefferson, WI
Feb 11, 2008
#37
  • Feb 11, 2008
  • #37
bloopbloob said:
keep your 2:73 gears, or switch back to them. dont rev past ~2000. take all the extra weight out you can. (this means no fat chicks too!) set timing to run lowest possible octane. get a tune up. properly inflated tires.... pretty much the same ways you do with any vehicle...
Click to expand...

I disagree with that statement (except for the fat chicks ). Unless you are commuting at 75+ on the freeway often, 2.73's are going to be more detrimental to fuel mileage than say a 3.27-3.73 gear.

To the OP, dump your codes, and do everything to make sure your car is in a good state of tune. If you can't get by paying for gas while getting 20-23 mpg, you probably need to get a job that pays a little better.
 
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