not sure if this counts... but ive noticed an extreme difference in gas mileage based on how long it takes you to accelerate to your desired speed. we all toke here, well mostly. it shouldnt be too hard for tokers to slow down! for instance: my buick with a 3.8 v6 gets 21 city 29 hwy on the sticker. i can squeeze a little above 40 mpg on a hwy if i start out correctly. about 30-33 mpg in the city if i take it super slow and roll up to intersections. but my car will freakin GO if u give it even half the pedal, then the MPG is is horrible. people in the u.s. forget this sometimes it seems, at least where i live , lol.