ok i got the 4.10's put on yesterday and im pickin up my car a little later, how bad will 4.10's really be on gas? and just out of curiousity how much does it cost to fill up your tanks and how often do ya do it, is $40 to fill mine i do it about once a week, prices in south jersey are 2.83 a gallon.

 

With 4.10's you will have a mechanical adavantage from a stop. With the gears, they will be doing more of the work to get your car going from a stop, thus your engine using less gas to make it go. HWY is different, sometimes good MPG and sometimes bad. With my 5.4 and 3.73's, i can get about 310-320 miles on a tank. I get 93 all the time, and have to with the tune, but i pay about the same as you,but I use 93 and it's $2.76 a gallon here.

Of course if you get on it, the MPG will suck.

 

I do almost exclusively city driving, and i get around 270 a FULL tank... usually i only put in six gallons (20 bux) and get >100 miles...
and thats with stock 3.23's

 

wtf im only gettin 200 miles on a full tank

 

same here lol..

 

but measure you actual gasoline usage, are you 'filling up' with 15.5 gallons everytime?

 

Thanks i'm new to filling up gas in a car.....lol.

That's with a full tank, can't put no more gas in it but not running over. I can get half a tank and get around 150 or more miles. I usually only drive my car 3 or less times a week, but when i do, i put about 50 miles (+- miles) on her per day. Last week i put half a tank in there, needle straight up,over 7 gallons worth and got 155 miles on, and that's with the needle ontop of the empty line,not before the line. I do more city driving than HWY. With 366TQ to the wheels and 3.73 gears, the motor sits back while my gears do the work from a go. And i don't really get on it that much, here or there sometimes. no one tries to mess with me on the street for some reason.

 

yea i messure about 15.5 and it lasts about 200 miles it sucks o well

 

That's 13 MPG, that sounds like my old 4.6 motor. It did crappy just like that. with the 5.4 swap it's now 20-21 MPG, which is pretty good.Also if you check out the nov 2004 5.4 swap into a mustang GT, they get about the same as i do. so im not fluffing anything. My friend has a 2003 GT and he can get around 18 MPG on his 4.6. hmm

 

im gettin a diablo tune in it to so do you think that will help?

 

Maybe, maybe not. How old are your spark plugs, coil packs, spark plug wires, fuel filter? also how many miles does your car/motor have?

 

93000 miles, should i replace any of them?

 

If they have never been replaced, i would replace all of them. I would get some NGK TR55 plugs, MSD wires and coil packs, motorcraft fuel filter. You could also get your injectors cleaned, just to make sure the spray pattern is at optimal use. If it was me, i would change out the fuel pump also, maybe a 155, 255 if your going to go bigger with the mods down the road. the fuel pumps can last a long time, but after so many miles, it does wear out a little. but you don't have to get a pump.
Also, i have 21lb injectors and a 255 fuel pump, just to meniton it.

If they cost to much, could go with OEM parts too, but usually they aren't to much cheaper.

 

i was going to get the msd coils and wires down the road anyway so now would be a good time to get them, how much would it help my motor?

 

If those parts are worn and not working 100% like they should, you could see a few more HP, better throttle response and maybe 1-3 MPG increase. Just depends.

With the new plugs, gapp them to .45

 

sounds good, im gonna have to pick them up with a knew fuel pump

 

cool, let us know how it goes.

 

I have a V6 and i get 230 miles on a tank

 

Maybe you need a set of plugs and wires. Thats what I was getting till I tuned it up.

 

i got either 27 or 32 mpg in my moms stock 04 v6 from dallas to oklahoma....bout 3 hr drive...dont know the miles....
cruise control was all i used
im pretty sure it was 32....but 27 is also im my head....

 

That's a full tank, 3 hours worth of driving? for 32mpg, that's 496 miles on one tank and 27 is 418 miles on one tank. Just asking, cause if your driving average 70mph X's 3 hours, that's 210 miles for those 3 hours of driving, that is around 14mpg. Of course it will depend on how fast you were driving.

 

In my car when I fist got it had 23k on it and barely got 200 miles to the about 12.5 - 14 gallons I would put in when I fill up. Since I've been modifying the car the milage has steadily improved. The biggest boost in milage was suprisingly enough form my 3.73 rear gears. It must be the fact that I'm in 5th more often or something, but i get anywhere from 230 - 250 miles out of the same 12.5 - 14 gallons now. High way milage only dropped about 1 mpg or so, but aroud town increased quite a bit. Of course a guy I met at a car show once with a 97 convertable Cobra told me that originally the 96 - 98 Cobras were suposed to have 3.73's form factory, but the big wigs at Ford vetoed that so they got the same 3.27's as the GT. Might be true, might not, who knows. Hope this helps.

 

Jesus...to the guy in the second post... 2.60 for PLUS? r u ****in kiddin me!... it's 3.25 for plus here!...

 

3.11 for reg... 3.31 for premium
luckily the pony runs on reg

 

Gears will improve your fuel economy in the city cause the gears help move the car from a go, a mechanical advantage, the gears do more of the work, less engine effort, improved gas.