MythBusters: Does Drafting Semis Improve Fuel Economy?

[zpiloto]

I wonder how many accidents there will be this week?

[DRW]

Dang! I missed tonights episode!

Then again, after reading this thread I guess I didn't miss much. Dracofelis's tutorial on Zombies was much more entertaining.

[caprice]

I watched it! I know we gotta say it and they gotta say it over and over again for liability reasons... but what so dangerous about drafting semis 50-100 feet? That is the distance most motorists are behind other vehicles. Don't truckers have twice the braking distance cars do? I wouldn't want the semi to be drafting me though!

I'm trying to say what if you are drafting but NOT tailgating?

In traffic, the trucker wouldn't notice, because you are just one of the hundreds of cars around him. In less traffic, if I wanted to draft, if i don't TAILGATE, but still am behind him, and I stay in his vision and pay real good attention to see if he doesn't want me there... thats when I would draft.

PS: Read that trucker forum link. "hand full of marbels" lol

[bbgobie]

I drafted a semi home last night and the FE was awesome, so I did it again this morning. Its all about finding a good one and hitching a ride. I didn't ride his arse, although I tested it out and the FE gains are enormous huge!

I didn't watch the show, but knowing mythbusters they used a gas guzzler un aerodynamic 80's ford or so? I figured the gains would be less in a more aero car like my RSX but my scangauge easily showed a 1LHK difference when I pulled out of teh draft which equates to about a 16.7% difference at the rate I was getting!

[Snax]

They used a Dodge Magnum. I didn't notice which trim level, but guessing from the wheels, I'd say it was an SRT (V8). Their control testing showed about 32 mpg at 55 mph.

[bbgobie]

Is the Magnum one of the new Big American cars that turns off half its cylinders when cruising to save fuel? So a V4 in this case?

Originally Posted by Snax

They used a Dodge Magnum. I didn't notice which trim level, but guessing from the wheels, I'd say it was an SRT (V8). Their control testing showed about 32 mpg at 55 mph.

[caprice]

Originally Posted by bbgobie

Is the Magnum one of the new Big American cars that turns off half its cylinders when cruising to save fuel? So a V4 in this case?

yes the hemi v8 does. I was guessing it was a v6. Did anyone notice the Camero Break the passenger mirror? they didn't say anything about it, but you could see it.

[rvanengen]

I only have a few questions after seeing that episode...

1) Why didn't they unbolt the bed (or cut the tops of the bed bolts)??

2) Why didn't they do a test at the minimum safe following distance?

3) How about at 70mph that most trucks run?

4) Why not do a more "real" test and fire the rubber at a WINDSHIELD?

5) Why not use a scangauge?

[parasonic]

Originally Posted by Bubba Bob

Drafting works. I found out last week while towing a trailer, you can get pretty far back and still feel the positive effects. However, if you get too close and a tire explodes... good luck to ya.

Also, as mentioned before, rock chips in paitn and glass are a PITA.

They are also testing a truck's trailer tire exploding, causing injury to a driver behind it "myth". Although, I dont know how thats a myth. Itll be interesting to see what they say. Ive seen blown tires turn DOT bumpers into pretzels, I have no doubt about it coming through a windsheild.

I once talked to a former truck driver about this. One time, he was in Texas, and he saw in his mirror that he blew a retread. He said that in Texas, they would NAIL you if the cops caught you leaving an alligator on the highway. So, he pulled over and went back to get it, and he found a station wagon stopped a little after where his tire blew up. What do you know...the alligator went through the windshield, went right beside the guy's head (I think that it actually scratched him), and went through the rear window. He said that if the guy had been a couple of inches over, he would have killed him.