Drafting can save you up to 45% in MPG

[M.D. Holloway]

Mythbusters tested the drafting myth last night - confirmed that drafting behind a semi will improve fuel economy. At 20 feet behind (I think) it improved milage by 45%. Even at 150 feet, milage improved in the double digits.

A very un-safe thing to do yet I wonder how many chuckle heads will do this to save money because they saw it on Mythbusters?

[masraum]

With the top down especially, I can feel a difference when behind a truck/SUV or semi, and to some extent regular cars. It's not really that surprising. Wasn't there some guy that went well over 100mph on a bicycle because he was in a draft behind a 935?

[Tobra]

There is a website about it, hypermileage or something.

My buddy used some of the techniques they propose and increased his fuel economy by 25% on his daily commute.

[competentone]

Originally posted by LubeMaster77
Mythbusters tested the drafting myth last night - confirmed that drafting behind a semi will improve fuel economy. At 20 feet behind (I think) it improved milage by 45%. Even at 150 feet, milage improved in the double digits.

A very un-safe thing to do yet I wonder how many chuckle heads will do this to save money because they saw it on Mythbusters?

I had to chuckle when I saw that episode. They were commenting about how "scary" it was to be following behind another vehicle so close.

They should have come to South Carolina to find a driver to do the testing! Horrible tailgating -- following literally 10-15 feet behind a vehicle -- is pretty much the standard here.

And no, the drivers are not trying to draft to improve fuel economy -- the tailgating we have here in South Carolina has to do with things in this state like the lowest SAT scores, the highest high school dropout rates, the highest teen pregnancy rates, etc....a whole lot of really stupid people here!

[Jims5543]

I tend to draft as much as possible when traveling on the interstate with the FJ cruiser. When I am in the Audi, get out of my way. I can get better gas milage with the Audi doing 90 MPH vs. the FJ doing 70.

[Porsche-O-Phile]

I'm sure that comment was added at the demand of the show's lawyers/insurers. In California, it's the same way - if you leave more than a 20' gap between you and the guy in front of you (regardless of speed), some jackass is guaranteed to whip into that gap and then slam on his/her brakes. Absolutely guaranteed. Most of the time it'll be some obnoxiously huge vehicle that you can't see around either to identify potential road hazards ahead too. I'm sure Jamie & Mark know it, probably drive like everyone else (protecting their lane position against those who think it's their God-given right to cut you off, nearly clipping your front bumper in the process), but they just can't say it on TV lest they (or their network) be liable for someone getting hurt.

Not that I'm advocating tailgating, but I know full well I tend to "close the gap" whenever I see someone pulling up alongside me (first step towards trying to cut me off). They either pass all of us or none of us - I think getting cut off is more dangerous than momentarily tucking in closer than normal, but that's just me.

[GDSOB]

Years ago, I used to pull a race car trailer with an old van with a gutless 302. Driving into a stiff headwind with the thottle pegged it would barely do 55 on the interstate. I could get it up to 70 in the draft of a semi at a reasonable distance 100 ft or so, but once I lost the draft, it was back to 55 and looking for my next drafting partner.

[Rot 911]

On a motorcycle you can actually feel yourself getting pulled forward when you get within 15 foot or so behind a semi. Also feel yourself getting scared.

[spencejm]

I'm with you on that one Kurt. You have to go through all the buffeting but once you get close enough it's just dead smooth. Plus, you hardly need any throttle at all. The problem is those trucks suck in all kinds of crap from the side of the road and spit them right out the back. The first time I got hit by a soda can backed me right off!

[azasadny]

I drove through Atlanta last March when I drove my 911 to FL and the cars there were all traveling within 10' of each other, changing lanes at random, talking on the cellphone, going 85mph + and it scared the hell out of me. Maybe they were trying to save gas?

[kaisen]

Truckers used to 'convoy' to draft each other to save fuel and maintain speed back before 500hp big-rigs were the norm. It helps the lead truck almost as much as the tag.

[M.D. Holloway]

Didn't someone get arrested recently for hitching onto a semi and letting it tow them for several hundred miles?

[Jeff Higgins]

Years ago I was attending an Advanced Rider Safety course for motorcycles. The instructor, with a perfectly straight face, stood in front of the class and told us the rule of thumb on the freeway was a following distance of one car length for every ten miles per hour. Most of the class erupted in laughter. She asked what we were all laughing at. "That'll getcha killed here in Seattle, honey" was the reply from the back of the room. "It's more like one car length no matter how goddamn fast yer goin', so the ass holes in cages don't keep cuttin' ya off."

[JavaBrewer]

A motorcycle drafting behind any vehicle the rider can't see around = early death.

[Porsche-O-Phile]

Have to agree. Around here the biggest hazard on the freeways isn't necessarily the vehicles, it's all the crap on the roads. The one time I've ever had to drop my bike it was because of road debris. The thought of following behind a large vehicle and having little/no warning before the bumper/muffler/exhaust/toolbox/gatorade jug/whatever it just "spanned" over comes flying out form underneath it at you is the one that scares me. One (of many) reason I can't stand SUVs and other vehicles that give no ability to see through/around. Even if you follow WAY back, it's still minimal reaction time to crap on the road. Best solution I've found is to make sure vehicles like that get behind me, not in front of me, so I can see what's going on ahead. It's easier for them to see around a little 'ol bike than for me to see around their Lincoln Navigator. If they don't like the fact I get in front of 'em, tough schit - it's not a question of "I want to be in front of you because my ego demands it" it's a question of "I NEED to be in front of you because my LIFE demands it".

[Jeff Higgins]

Originally posted by Porsche-O-Phile
Have to agree. Around here the biggest hazard on the freeways isn't necessarily the vehicles, it's all the crap on the roads. The one time I've ever had to drop my bike it was because of road debris. The thought of following behind a large vehicle and having little/no warning before the bumper/muffler/exhaust/toolbox/gatorade jug/whatever it just "spanned" over comes flying out form underneath it at you is the one that scares me. One (of many) reason I can't stand SUVs and other vehicles that give no ability to see through/around. Even if you follow WAY back, it's still minimal reaction time to crap on the road. Best solution I've found is to make sure vehicles like that get behind me, not in front of me, so I can see what's going on ahead. It's easier for them to see around a little 'ol bike than for me to see around their Lincoln Navigator. If they don't like the fact I get in front of 'em, tough schit - it's not a question of "I want to be in front of you because my ego demands it" it's a question of "I NEED to be in front of you because my LIFE demands it".

Right on. I see guys on bikes every day right behind something I know they cannot see through or around. Or riding in some one's blind spot, or whatever. I will go a long ways out of my way to get in behind a car I can see through or over. I find I usually react to crap in the road even before they can, if they do at all.

I will, however, "defend" my space when riding in traffic. To me, it has always seemed the lesser of two evils to leave a small enough gap in front of me that it is simply not appealing to those looking for a gap to shoot. The only time I've been down on a bike was on the freeway, when some one overtaking me just had to shoot that gap. He miss-judged it and clipped my front wheel with his step bumper. That was 27 years and about 300k incident-free miles ago. I may annoy or frighten some folks when I follow them, but they are not wrapped around the outside of their vehicle, like some Aztec sacrifice waiting to be disembowled. I am. And I'm safer if I follow closer.

[David]

Not that I'd do it today, but I drafted an 18 wheeler from San Marcus to Austin many many years ago in a company van so I didn't have to stop for gas. I was a bit closer than a car length, but I almost didn't have to touch the gas pedal. When I pulled out for my exit, the driver made it clear he wasn't impressed with my little stunt.

[mattdavis11]

Originally posted by 125shifter
Not that I'd do it today, but I drafted an 18 wheeler from San Marcus to Austin many many years ago in a company van so I didn't have to stop for gas. I was a bit closer than a car length, but I almost didn't have to touch the gas pedal. When I pulled out for my exit, the driver made it clear he wasn't impressed with my little stunt.

Me too, on the very same stretch of roadway in a Dodge Ram truck. Although I did it many times then, I wouldn't do it now.

I had a Mercury Sable that would track the center lane from just north of San Marcos to Onion Creek. Set the cruise at 74, and let it go.

[sammyg2]

It's a shame that drafting is such a stupid thing to do.
Pretty soon we will be seeing or reading all about idiots who were killed trying to get 100 mpg by drafting. it's called hypermileage or something like that. I would call it the next chapter in darwin's book, except that i don't believe in evolution.

[competentone]

Originally posted by sammyg2
It's a shame that drafting is such a stupid thing to do.
Pretty soon we will be seeing or reading all about idiots who were killed trying to get 100 mpg by drafting. it's called hypermileage or something like that. I would call it the next chapter in darwin's book, except that i don't believe in evolution.

Actually, with the direction the technology is going in cars, it will probably be just a few more years before computer-radar-controlled drafting can be done safely.

You'll get on the highway and essentially put the car on "auto pilot."

If it were done on a large scale, just think of the overall fuel savings!