Which will have better gas milage?

Question

If i drive a car at higher rpm and follow a diesel with a trailer to reduce the drag of air like in nascar where they follow real close (but im not intending to drive that close) :P or lower rpm and not following anything?

Answer 1

There's a number of things about your question.

Depends on how close you follow for one thing. Most people do nor follow closely enough for it to really help. You need to almost be on the truck's bumper for it to really help, other wise it's actually a hinderance.

Second, if you drove the same speed behind the trusk and then *not* behind the trusk, you'd get a little better mileage. BUT, if you didn't drive behind the truck, but drove faster.....you could go faster and achieve the same mileage essentially, but not that much faster.

I guess for arugment sake what you propose is valid, but in practicality why bother? Another point is, if you drove faster behind the truck, how fast could you really go. Most rigs don't travel that fast, unless you live near the plains or something like that.

Just a few thoughts.

Answer 2

The question doesn't make sense. Are you suggesting you should follow a truck in a lower gear than you would use when not following a truck? That's just idiotic. If you traval at the same speed your milage will be just slightly better (like a half mpg) when following the truck - but as others have mentioned, you have to follow extremely close, and that's really not very safe. It probably pisses off the trucker as well...

It's really not enough of a fuel saver to make it worth doing unless you can get about 2 car lengths behind a truck going about 80 mph (sounds easy until you realize how close that really is - especially at 80 mph).

Your best gas milage will be achieved at between 50 and 60 MPH, no matter if you're tailing somebody or not. Often, the more gears your car has, the better your highway milage will be (this is why big trucks have an absurd amount of gears).

Answer 3

This question isn't specific enough to determine what would technically be better in gas milage. (You need mph/road conditions/where are you driving at).

If you're on the highway/interstate you should NEVER tailgate someone. You dont' save gas going 65 mph-85mph by drafting (like in Nascar) and you put yourself at a high risk of causing a wreck.

The best way is drive a constant speed. Excelleration is the most fuel burning part of driving. If you can drive the same speed and not have to speed up and slow down, your mpg will be better.

Best of luck to you.

Answer 4

I would say lower rpm (but it depends on how much lower) for example if your following that trailer at 5,000 rpm just to get some turbulence you will blow a lot more gas than if you just drive alone at 2,000 rpm

Answer 5

The friction HP (lost) in a piston engine is directly proportional to piston speed. Ergo, the lower rpm you can use to get the required power, the lower the fuel flow rate for that power.