ToplessGT

its all relative, I have 3.73 which is worse milage than stock 2.73. 4.10 are around 300 rpms more at highway speed, 4.30 is a little higher. The higher the rpm, the more gas gussling, but the more fun. either way, anything but stock is better.... oh, and trust me, gas mileage wont matter. you'll be mashing the gas pedal anyway bro

ToplessGT

oh, but some people here will say there gas mileage dropped by 2 mpg or so... i cant tell on with 3.73's. gunning it from stop light to light is getting me around 14 mpg.... but its fricken fun as hell

03sonicgt

I'm not all that worried about gas mileage, I just haven't heard of alot of people getting 4:30's.

jsolor7

smaller gears (higher number) actually gives you better street mileage. I went from 3.27 to 3.73 in my old 5-0 and got better gas mileage by a couple mpg! I drove mostly streets though.

Dan04COBRA

It depends on the driver for the MPG you'll end up getting.

I averaged OVER 15mpg in town with 4.30's. Starting in 1st, skip to 3rd and go to fifth. Didn't notice much of a drop when I didn't short shift...

As for the highway, I never spent more than 150 miles round trip on the highway with 4.10's or 4.30's so I can't tell you how I did for highway mpg. If you drive the speed limit and don't mat it all the time, you won't see more than a 2mpg drop.

spederman

I am getting 3.90's put in saturday. It all depends what your plans are for your car. For me, i plan on having a procharger by the end of the year. I didnt do 4.10's because i dont want to run out of gear in 4th at the track or street. My calculations were based on my tire size. I know i could run a taller tire, but dont really want anything bigger than my already 26" 295/35/18's. Plus i dont really need to be spending the cash on another set of wheels/tires and swapping them out when i plan on racing. So for my calculations in 4th at 6K i would top out at 113mph for 4.10's and with 3.90's i would be at 120mph. Since with a procharger i will be trapping that high, i chose the 3.90's.

If i were to stay N/A then 4.10 for SURE. Because the only difference in rpm vs the 3.90 is 125-150 which is nothing and not really saving any gas on the hwy.

2000GT4.6

not that I disagree with 4.10s, but I am willing to bet 20 bucks that 99 percent of people could not tell the difference between 3.90s and 4.10s in an identical setup.

2000GT4.6

Christ, 15 MPG city? I get that with the blower on!

hell, I was getting like 19 MPG city before the blower.

tcuallstar

id be lucky to get to 200 miles on my trip before the low fuel light comes on, thats all city driving and i barely ever go over 2000 rpms.. ive been trying to figure out what the hell is wrong with my stang for a while

GSXRIntensity

I could get 250 on a full tank w/my GT before the h/c/i install. About 300 when it was stock. Now, I fill up before I hit 150 on the trip. I had a 147 and I was getting nervous about finding a Mobil.