• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2.3L (N/A & Turbo) Tech

Gas saving power adders

  • Thread starter Thread starter Twilight Blue
  • Start date Start date Aug 8, 2005
T

Twilight Blue

New Member
Aug 3, 2005
56
0
0
Aug 8, 2005
#1
  • Aug 8, 2005
  • #1
I have altered the factory set-up for the air intake by removing the bottom of the air box and using just the top with a K&N air filter, and I removed the silencer. I have pretty good power now, but terrible gas milage. The power gain was not worth the amount of gas being used. I can lay the hammer down and actualy watch the gas gauge go down a bit. Wasn't improved air flow supposed to help increase milage? Also, aren't headers supposed to help also? I don't have a header, but was just wondering. I'm going to put a Fram paper filter in and return the air intake back to the way the factory had it and see if milage returns to normal. Any thoughts?
BTW, I've got a 50 series Flowmaster and a free flowing cat.
 

Stinger

Founding Member
Jul 7, 2001
7,754
24
118
Basehor (Kansas City), KS
Aug 8, 2005
#2
  • Aug 8, 2005
  • #2
It shouldn't make your mileage go down...something else is wrong.
 
B

BELL

Founding Member
Feb 21, 2002
722
0
0
California
Aug 9, 2005
#3
  • Aug 9, 2005
  • #3
vacuum leak?
 

Mr. Merk

New Member
Aug 5, 2005
72
0
0
NW Arkansas
Aug 9, 2005
#4
  • Aug 9, 2005
  • #4
i'd bet thats it
 
B

BELL

Founding Member
Feb 21, 2002
722
0
0
California
Aug 9, 2005
#5
  • Aug 9, 2005
  • #5
my old lx had the same mods and i got probably 2-3mph improvment. never lost fuel milage tho.... i think theres more to this...
 
J

joebford

New Member
Aug 15, 2004
15
0
0
Aug 10, 2005
#6
  • Aug 10, 2005
  • #6
By cutting away the airbox, you are now drawing heated air from inside the engine compartment. This nullifies any gain you may have imagined from more airflow. You want cooler air for the most benefit.

Laying off the accelerator will increase mileage.

Headers will help if you keep the rest of the exhaust system in perspective. You want to get rid of backpressure without effecting velocity unless you want your power band to be at higher rpm. joe
 
B

BELL

Founding Member
Feb 21, 2002
722
0
0
California
Aug 11, 2005
#7
  • Aug 11, 2005
  • #7
by removing the intake silencer and having a better flowing airfilter and some exhuast, you will increase air volume to the engine, 10-15 degrees difference of outside air temp to engine bay air temp with this little motors doesn't come into play. keep in mind that the difference in air temp while moving is minimal when driving 30-45 mph as air flows into the engine bay, you dont measure air temp at a stop...


its been a while since i had the lx, with the svo i've given up on fuel mileage juice it around is too much fun...
 
J

joebford

New Member
Aug 15, 2004
15
0
0
Aug 11, 2005
#8
  • Aug 11, 2005
  • #8
BELL said:
by removing the intake silencer and having a better flowing airfilter and some exhuast, you will increase air volume to the engine,
Click to expand...
Air volume to the engine is of little value if the engine can't do anything with it. Air will flow no better than its smallest restriction. If it is a MAF engine, that is a small restriction, and when it gets by that, it has to contend with the cylinder head, the same with most 2.3's.
10-15 degrees difference of outside air temp to engine bay air temp with this little motors doesn't come into play.
Click to expand...
Air temperature has more effect as it affects thermal effeciency of the engine.
keep in mind that the difference in air temp while moving is minimal when driving 30-45 mph as air flows into the engine bay, you dont measure air temp at a stop...
Click to expand...
If the engine compartment had laminar flow, this would be true, but the air swirls throughout the engine compartment. Because of this effect the Merkurs have a plate that bolts to the front of the front crossmenber to create a low pressure area in order to get a proper flow thru the radiator and carry some of the engine heat down and out of the engine compartment. Merk engine compartments get scalding hot. Many folks throw this plate away as it becomes damaged not knowing what its purpose is. joe
 
T

Twilight Blue

New Member
Aug 3, 2005
56
0
0
Aug 11, 2005
#9
  • Aug 11, 2005
  • #9
joebford said:
By cutting away the airbox, you are now drawing heated air from inside the engine compartment. This nullifies any gain you may have imagined from more airflow. You want cooler air for the most benefit.

Laying off the accelerator will increase mileage.

Headers will help if you keep the rest of the exhaust system in perspective. You want to get rid of backpressure without effecting velocity unless you want your power band to be at higher rpm. joe
Click to expand...


I didn't cut away the air box, I just removed the bottom square part and just used the lid to hold the K&N air filter. The power increase was pretty good, but the milage went bad. I don't see how the engine heat is an issuse. The cold air intake kits K&N and various other air filter companies make for Mustangs place the open ellement air filter in the same place as factory, but just without an air box. They increase the power despite it being hot in the engine compartment. And the old carburated cars of old had the air being sucked into the engine smak dab in the middle of the engine compartment, and we all know how powerfull those mustangs were. As for the accelerator, my car is a 2.3L N/A with an automatic. I have to push it hard. When getting on the highway, or passing on a rural road, I have to give it all its got or things are going to get dicey. And the header, i'll take power at any RPM, just give it to me!
 
J

joebford

New Member
Aug 15, 2004
15
0
0
Aug 11, 2005
#10
  • Aug 11, 2005
  • #10
Twilight Blue said:
I didn't cut away the air box, I just removed the bottom square part and just used the lid to hold the K&N air filter.
Click to expand...
It doesn't matter how you did it, the end result was the same.
The power increase was pretty good, but the milage went bad.
Click to expand...
The seat of the pants dyno almost always tells you what you want to know. By playing with the additional power you think you have is why your mileage went south.
I don't see how the engine heat is an issuse. The cold air intake kits K&N and various other air filter companies make for Mustangs place the open ellement air filter in the same place as factory, but just without an air box. They increase the power despite it being hot in the engine compartment. And the old carburated cars of old had the air being sucked into the engine smak dab in the middle of the engine compartment, and we all know how powerfull those mustangs were.
Click to expand...
I'll not try to educate you on the workings of an internal combustion engine in this forum, but suggest you do some research on the subject, then you will understand the relationship of intake air temperature to combustion effeciency. I will mention intercoolers, hood scoops outside the car on race cars, ice canisters, etc.

The items you mentioned are not cold air intakes if they are drawing underhood air. Most have a baffle of some sort to provide some isolation, but a true CAI takes air from outside the car.

The older cars were powerful, but didn't get into CAI's until the later years. Then you saw hoses going from the air cleaner to outside the car, shaker hood scoops, etc.
As for the accelerator, my car is a 2.3L N/A with an automatic. I have to push it hard. When getting on the highway, or passing on a rural road, I have to give it all its got or things are going to get dicey. And the header, i'll take power at any RPM, just give it to me!
Click to expand...
I have a 1989 2.3 convertible with auto, and don't have any of the issues you mention. It's not a V8 with tons of power, but it gets the job done, plus I get from 27 to 30 mpg. joe
 
T

Twilight Blue

New Member
Aug 3, 2005
56
0
0
Aug 11, 2005
#11
  • Aug 11, 2005
  • #11
I have a 1989 2.3 convertible with auto, and don't have any of the issues you mention. It's not a V8 with tons of power, but it gets the job done, plus I get from 27 to 30 mpg. joe[/QUOTE]

Then something is definately wrong with my engine. Mine's a 1991 with dual plugs and 105HP @4,600RPM. A 1989 is supposed to have 88HP. Mine's just gutless. My gas milage has never been very goo either.
 

raceguy13

New Member
Jul 9, 2005
12
0
2
Albany, Oregon
Aug 14, 2005
#12
  • Aug 14, 2005
  • #12
get a v8. if you dont get good mileage might as well have power.
 
You must log in or register to reply here.

Similar threads

J
Engine Running like crap :(
  • justadude07
  • Sep 27, 2025
  • Fox 5.0 Mustang Tech
Replies
8
Views
309
Fox 5.0 Mustang Tech Oct 19, 2025
DadLife0724
S
Fox '87 GT can't get to stay running
  • spilly
  • Mar 29, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
26
Views
570
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Apr 25, 2026
CAMTWO1070
SURGING IDLE / NO IDLE CHECKLIST FOR 1996–1998 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
671
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
SURGING IDLE / NO IDLE CHECKLIST FOR 1999–2004 MUSTANG GT (4.6L 2V) - Work In Progress
  • Noobz347
  • Aug 30, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
0
Views
811
1996 - 2004 SN95 Mustang -General/Talk- Aug 30, 2025
Noobz347
F
1990 mustang GT, essentials to making a 5,000 mile round trip (Michigan to California, and back)
  • FreeMustangProject
  • May 8, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
19
Views
850
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 14, 2025
hoopty5.0
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2.3L (N/A & Turbo) Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?