Need help on mods that will keep good gas mileage?

[1990StangGT]

Ok here is what I got, I bought a 91 LX 5.0 5 speed. All stock car. Now I plan on some mods since this will be my daily driver I want to keep the gas guzzling issues down that these cars usually have when modified, or so i experienced with my 90 Gt. Since I did not do many of the mods on my Gt I don't know alot. What I do know is what I would like to do to it. I was thinking a upper and lower intake, maybe trickflow somthing mild RPM range,wires, a throttle body and throttle body spacer, cold air intake, pullies, cat back, keep stock h pipe and get some headers. Will I need to get a new fuel pump or regulator, or injectors? What Rpm range intake should I get? And will all these products work well enough to where I can get 20+mpg? Also down the road I would like a supercharger, agian being a daily driven car would this be recommended? And with say 6psi would i still get resonable gas mileage?

 

[PRO50SC]

And you're worried about gas mileage!!!

 

[1990StangGT]

If I wanted comments like that I would of said, who can make the best smartass comment possible in this forum? I am just wanting some common help sorry if I would rather spend my hard earned money on better things.

 

[95GTV8]

well the stuff you mentioned is fine, but anything like induction that gives you more airflow is obviously going to require more gas such as an intake. Some things that won't decrease gas milage, UDP's, Headers, O/R Pipe, CAI is pretty much useless, get a stock box remove silencer and add K&N.

 

[afast93stang]

My engine only has pulleys, 1.7 Cobra rockers, shorty headers, O/R-H pipe and dynomax mufflers, and a CAI. It still has the original 3.08 gears and a 5spd and I still get 25mpg on the highway. Not bad for an engine with 183k miles on it

 

[Henceforward]

New plugs, new plug wires, new fuel filter (WIX is fine), new air filter (K&N), remove and clean the injectors, clean the IAC, clean the MAF needle, proper tire pressure, use 5th gear all the time. Check the MIL for EGR codes, dump all the codes and check for stuff like code 33. New thermostat, new belt, check the tensioner pully for worn bearings

Clean out the interior, remove all the junk, papers, pennies, trash etc.

Don't run the A/C

Stick with 2.73 gears, or 3.08s at the most... I ran 3.08s for a couple of years, 23 MPG Highway was the best I ever saw with 19Lbs. injectors in 5th gear.

Start with the basic tuneup stuff first.

 

[1990StangGT]

I am really shocked you got 25+. I am was not even looking for that much, just somewhere around 18-20 hwy and I would be happy. I see all the B/S about CAI and underdrive pullies bringing your fuel mileage up it is basically a load of **** I was just talkin pretty much about the intake and what I would need to do when installed? And what i need to do to get it running fine. If i need a fuel enhancement? Or will it bolt up and work fine and not cost me less than 9mpg.

 

[kpack5982]

Well to tell you the truth, you'll prolly get about the same or better gas mileage with the intake and exhaust, that usually helps with less restriction and better fuel consumption. Right now with my current mods I'm getting about 24-25 highway mpg, although the intown driving really hurts me (I like to get on it and hear my exhaust ). I too am eventually thinking about a power adder, but it is still up for grabs. I figure that I'll do what I need to for now, cause who knows how long it'll take to do the other stuff and accumulate the funds. From what I've heard supercharging will affect the gas mileage in the negative slightly, just for having the extra pull on the engine to run the supercharger, I don't know correct me if i'm wrong someone. One friend of mine ran shorty headers, mac h pipe and flowmaster with tips and he actually got 2-3 mpg better on his daily commute.

I also heard there is no need to get a bigger fuel pump or injectors unless you're running over 300 horses, or in your case, eventually upgrading with a power adder.

 

[8950HO]

Back when I was a young teenager,an older mechanic who was into fast car`s said these wise words...
"The faster you want to go,the more gas you`re going to burn".

The basic easy bolt on mods won`t hurt gas mileage and may even help it,but once you get into more serious mods,good gas mileage goes down the drain .

 

[ninety15.0]

I dont think all of what has been said is true. Any time you make it easier for air to get into and out of the engine will increase efficiency. By adding a full intake, TB and exhaust you will most definately increase your milage. Theres no need for a CAI, just get a k&n and remove the silencer it will work just as well. There is also no real need at this point to do headers, the stock tubular manifolds will work just fine for you. Your money wil be better spend on a good catted h or x pipe and a good flowing cat back....preferably not a baffled muffler. Next comes a real good tune up, new plugs, wires, t-stat, rotor, cap, fuel filter, pcv valve (and screen!) and then toss some injector/fuel system cleaner in the tank. I dont know what kind of driving you do, whether its mostly highway or mostly in town, but i would ditch the stock gears for either 3.27;s if you do mostly highway driving or 3.55's if its mostly around town. Stock gears suck around town because it takes so much pedal imput to get the dam car moving....but anything higher than 3.27's on the highway are going to negatively impact your milage. just to let u know with my stock motor with just full exhaust, k&n, and a good tune up i got 27-28 mpg cruisin at 70 on the highway. With my new motor and 3.73's i still got 25+ while cruisin at 70 on the highway. So performance parts alone will not cause u to loose milage...its mostly how you drive...the gas pedal is nothin but a valve, the more you open the valve the more gas goes in....if you make the motor more efficient and youre still conservative with the gas pedal, then 30mph isnt impossible! good luck man

 

[vristang]

All the "gear head" stuff has been mentioned, so I will just mention an e- fan.
Not only more power when you hit the throttle, but better economy too. Synthetic fluids supposedly help reduce friction in the drivetrain. I am not sure if you will see fuel economy gains from it though, as I have never seen any solid data.

jason

 

[HISSIN50]

Only drive downhill.

 

[Black1987Stang]

Im surprised no one said, its a mustang if ur worried about gas mileage buy an import or something like that , I hear ya though, i got to drive mine every single day and its no fun putting gas in it all the time although it kinda makes it worth it to have power on tap ..I would go with intake, exhaust, gears, throttle body, maybe bigger mass air flow meter as in size to help out the airflow but still set up for the stock injectors(if u r mass air anyway, didnt look), underdrive pullies, electric fan, and most of all having a healthy engine, good tune-up, and getting rid of any codes and i dont mean by erasing them...the right way by fixing whatever is wrong...an egr code could be killing mpg if u have a defective egr valve/sensor etc. ....and of course to keep ur foot out of the gas, i have my dads oldschool vacuum gauge and im always looking at it to see how much of a load there is on the motor etc. i try to keep it above 12 inches of mercury of vacuum when changing gears and driving.

 

[1EVIL88VERT]

with all the crap thats done to my car....around 300rwhp i still get 24mpg at 75 mph with 4.10's!...just keep your foot out of it! One other thing that i'm not sure has been mentioned is dropping weight....less crap to push = less pedal required to move it.

 

[the98stang]

Exhaust and a CAI should help your mileage a little. Put in a new fuel filter and use seafoam. Maybe shift at earlier points?!