its a basic formula. you take a certain speed lets say 50 MPH. Then you compare the gears. lets say 3rd, 4th, and 5th. Under 3rd gear you would be at (these are not realastic numbers) 5,000 rpm, under 4th gear you would be at 4,000 rpm, and in 5th you would be at 3,000 rpm. Naturally in 5th gear, going 3,000 rpm, making the engine work not as hard as it would in 3rd gear going 5,000 rpm, you will optomize your mileage by going in 5th gear whenever possible, thus making your engine work less hard thus saving gas.
Thanks hotshot. I tested my mpg by trying to drive on one tank full as "easy as possible" shifting to 5th around say 40mph+ (all in town driving).... amazingly, I got a whopping 0.3mph increase vs. a full tank of "normal driving" (....mix of 4th/5th gear cruises at 40+mph) and an occasional romping on it---for a taste of Rice-er-Roney).
I do all city driving (granted quite a few lights to stop at in town)...and averaged from 15.8 when new and as I just turned 3500mi on the odometer... now 16.2mpg! Ouch.
I didn't buy my stang for gas mileage, but I see GTers with 19mpg city and wonder -- what's the secret....In the interim, I'll be looking for those declines in the road, drive in a taller gear, put er' in neutral ahead a few miles in front of the intersection, maybe a push-start of two and jump in .....LOL......
Also, don't know (doubt it) if related, but I just installed GTA axle-backs and did notice (maybe I'm losing my mind here) a little less grunt off-idle and also in the lower rpms.... who knows, maybe it's the heat here in Texas!! OR - maybe its about time for CAI+tune
Yeah, that's it, more air more efficiency in mileage...