Has anyone change the 3.73 gears

[mitchster]

Wondering if anyone change the gears for track or to make the car more fuel efficient. Also there was much discussion about the best gears to go with a supercharger on the Mustang GT. Will anyone be more incline to add a supercharger after the GT500 comes out. I was thinking a set of 3.31 or 3.55 would be better if you add more power and a set of 4.30 for tracking. Just curious cause I will be looking to buy a GT350 early next year.

 

[ArkLightning]

The only thread I've read on this subject was a recent experience changing to a lower rear (4.11). He seemed pleased with the results. I would be wary of putting a higher rear end in the car. The motor thrives on revs and a higher rear end will just hamstring it and also make it a bit touchier to drive in stop and go traffic. Also, compared to my 2012 GT with 3.31/6M, the GT350 transmission is much, much better optimized to the engine and the 3.73 rear. Actually, if you are worried about fuel mileage and higher gearing I would look at a GT or GT performance optioned car instead of a GT350.

 

[galaxy]

I did a short road trip on mine already and if you’re on the highway and driving like a Normal person I could average 20+ fairly easily. Think i saw a 22 average on a whole tank. Don’t know why you would have goals better than that in a beast like this.

Also keep in mind higher gears/lower rpms doesn’t necessarily equate to better fuel economy. You get the engine out of it’s sweet spot and now it’s bogged down, which will use more fuel than the inverse. Rpm’s is but just one factor in the equation.

I have an ‘02 F150 I went from 3.55’s to 4.10’s for towing performance and without a trailer during normal driving, my fuel economy went UP an average of 2-3mpg across the board in all driving conditions.

 

[GT Premi]

...

I have an ‘02 F150 I went from 3.55’s to 4.10’s for towing performance and without a trailer during normal driving, my fuel economy went UP an average of 2-3mpg across the board in all driving conditions.

Your fuel economy went up because you were subconsciously using less throttle for the same rate of acceleration. When I first installed my Whipple, I was getting killer mileage out of my GT500. I thought it was weird that more power yielded better fuel economy. Then it hit me that I wasn't dipping into the throttle as much for the same acceleration that I was used to with the stock setup. After I got used to the Whipple, my mileage took a commensurate hit. It's abysmal now. It's tempting fate just trying to get 230 miles out of a tank now. Push it out to 250 miles, and there's literally only a few ounces of fuel left in the tank when I refill it.

 

[ANGREY]

I've seen other discussions about running 411's but never going smaller than the stock 373's. Going smaller would make the car even more difficult to launch/start than it already is. These cars are fairly difficult to launch with as wide as the gear ratios are to match the wide rpm range and the steep torque curve at the bottom end.

Too much RPM and you spin. Not enough and you bog. Very tight window, but obviously not what the car is designed to do.

My car runs like 87 at 2500 rpm in 6th and 103/104 at 3000 rpm. That's plenty of gear.

Running 411s would reduce the time between gears and make the shift cadence more like most "traditional" manual V8's. I see so many guys short shifting because they're used to the pace of rowing of cars that redline in the mid 6's.

I happen to like the overdrive and tranquility of the 6th overdrive. Running 411s would definitely liven the car up a bit, but for long(er) trips, you'd definitely notice a drop in fuel economy (all driving conditions) and for those of us with aftermarket exhaust, you'd need hearing protection for long trips cruising above 70.