What is the real difference between the auto and standard pinions?

[jerd_hambone]

Anyone know exactly how much of an acceleration difference? MPG gains?

I have an auto gear that I'm considering swapping into my car, as I don't have the space or place to drive like a maniac, the car will be my daily, and will rarely see any spirited driving.

I'd use it mostly to keep rpms down, considering we have stop lights every 1/16 mile, standard speed limit is 35-45, and I'll probably rarely take the car over 55-70 mph.

With gas prices well over $3 a gallon here, I'll take a hit in the seat of the pants to save a hit in the wallet, unless it will be so slow that I'd not be able to bare it haha