Conserving gas? - BMW Forum

donutchow · 08-04-2003, 08:27 AM

So I usually fill up my tank after I go 300 miles on it, which turns out to be just under 30mpg usually. But I'm at just over 300 miles and found out that I am running low on gas because I let my girlfriend drive my car for an hour so she can practice stick. I really don't want to run out of gas and couldn't get it before work, and I need to make it back home (there's a really cheap gas station right by my house). What speed on the highway should I maintain to get the gas mileage? I know I should stay under 70mph, but there was this tour bus going 75mph and I was drafting right behind him to save gas. I figured I was so close to him that I was getting over 50mpg, but I'm not really sure how that stuff works. But my car felt much more powerful behind the bus when I accelerated, it was great! So is it worth it to go slower to conserve gas or to draft behind a huge truck??

GreenDragon · 08-04-2003, 08:41 AM

Supposedly the speed limit (55) was put in place because you get the best gas mileage at that speed (if I remember correctly it was instated when the gas prices went through the roof in the 70's(?) or so).

lwebb12 · 08-04-2003, 11:51 AM

yes green dragon that seems right. drafting a big vehicle is always a bad idea if you are too close. saves on gas mileage though because your engine doesnt have to work against 75 MPH winds.

AZ325Ci · 08-04-2003, 01:36 PM

why not just go and fill her up?

fatty · 08-04-2003, 01:38 PM

its the "sling shot" thingy that the nascar guys do, but then the nascars guys arnt gonna slam on the brakes to pull off for the next junction......

theres loads of other things you can do to conserve fuel.....

keep your windows shut (less wind resistance)
keep your car polished (less wind friction/resistance)
change sooner instead of close to the red line....
drive with lower Rpm's
get the bus :lol: :lol: :lol: :lol:

m42technic · 08-04-2003, 03:22 PM

Dont forget to check your tire pressures!

2.link · 08-04-2003, 03:26 PM

when going down hill keep the clutch on....roll down it no matter how long it takes :P

triggrhaapi · 08-05-2003, 01:39 AM

according to the car's computer, I get best mileage (45mpg on a flat plain under light throttle with no turbo boost) at 75-80mph

donutchow · 08-05-2003, 08:26 AM

Quote:

Originally posted by triggrhaapi@Aug 5 2003, 03:19 AM
according to the car's computer, I get best mileage (45mpg on a flat plain under light throttle with no turbo boost) at 75-80mph

that seems awfully fast to get optimum mpg

Agammamon · 10-06-2003, 01:26 PM

Actually that sounds about right. The consumption rates on most modern cars doesn't go through the roof until well past 85. Most cars get fairly close to the same MPG at 85 as they do at 55.

woobiee · 10-06-2003, 01:59 PM

i think GD is right about the speed limit.

about drafting...i have been told at such a low speed (you say 55, 75 mph etc) drafting is kinda useless since the benefits of it is so low and insignificant.

Hamann 325i · 10-07-2003, 10:10 AM

how close you gotta be to draft?

DesmoBob · 10-07-2003, 01:28 PM