Powerful Plus Mileage

[El_Diablo]

im too heavy on the throttle, with my 3100 i usually get between 13 and 18mpg and 24mpg max on the highway... but hey! i got 22mpg and made the trip from pittsburgh to columbus (188 miles) in only 2 hours

[PCGUY112887]

Dang, the 18mpg I listed for my modified 3500 was for 100% city driving.

How are some of you guys getting such bad MPG with stock engines?

[IsaacHayes]

Maybe they need new O2 sensor and other tune-up related stuff? Worn transmission? Heavy stereo system/payload? :P

18mpg in the city for a 3.5l with a cam isn't too bad! Have you got it tuned in 100% yet?

[El_Diablo]

never said my engine/car was stock, lol

you have to consider the fact that im at more than 60% throttle during most of my city driving and the average for that trip was 94mph and i certainly wasn't able to maintain that constantly but i did spend a bit of time over the 100mph mark... considering i have a 4t40e that doesn't like to kick down and cruise at those speeds it kinda makes sense, hell, most of that trip was spent between 2k and 5k rpm with maybe 20-30 minutes spent cruising in the sub 2 rpm range

[19Cutlass94]

I usually always get 25-26mpg around town and mid 30's on the highway... But I think that will all change when I get my motor swapped in

[IsaacHayes]

How bad does a big cam kill your MPG? Like can you have a decent power cam with some lope and still have good MPG like stock? It seems my mods have only helped my mileage.

[Rhedalert]

One of the biggest influences to fuel economy (especially highway) is Weight, Drag, and in some cases gearing. Reduce the vehicle weight, make it more aerodynamic, and keep the engine at a good cruising rpm range and you'll improve it big time, no matter how big the engine size.

[torq455]

i get 22-26 in town depending on outside temps. best highway was 31 on one tank mostly at 75 mph and about 1.5 hours (both ways) on extremely steep hills. like down shifting to 3rd at about 1/2 throttle.

type of tires--compound and width, and psi factor in as well.

[JohnnyReb]

Plus just turning an engine slower does not mean it is using less fuel. The less mechanical advantage you give the engine through the gears the more torque it must make. To make torque you must burn fuel so you just lost your goal.

To make more hp you must burn more fuel. tq and hp are two diffrent things. Look at the way olds built most of the rear drive cars. Big engine and small ratio rears. You could find a 455 turning 2.73's getting good mpg. Look at the L98 Tuned port engine cars. low hp, high torque, od and small ratio's 30 mpg highway.

[85_Olds_Ciera]

The best way to get economy is a light car with....

YouTube Video: The Aptera typ-1



The claimed fuel efficiency of 230 mpg at 55 mph (1.0 L/100 km at 90
km/h) would make it one of the most fuel-efficient cars in the world.