Dubbayoo

When I'm on the highway if I can speed up or slow down 5mph to draft someone and save some gas I try to do it. I stay 2-3 lengths behind always but I figure it's good for another 5-10 miles per tank.

What say you?

urbanknight

Behind the unpredictable drivers of So Cal? You're nuts! I used to draft off of big rigs until I did an experiment where I did it consistently for an hour up the I-5 and found no measurable difference in mpg at the next station.

But why is this about driving in a car? Shouldn't it be about drafting to save energy on your bike?

powstash

My dad taught me to draft off diesel trucks when I was a teen. I never knew he was a roadie at heart.

I do it from time to time - or at least pay attention to opportunities - especially when climbing up a hill and a F250 passes by and my subie needs a little boost I'll swing in behind the truck for a bit if I can.

rasamatoo

Mythbusters did a myth test with drafting. I think they showed that you can get 50% better mileage by drating 1.5 m behind a bigrig. Kinda dangerous, but at those outrageous gas prices, maybe...just maybe...

No seriously, don't.

ShadowGray

I would never draft behind a tractor-trailer or anything with more than 4 wheels... that's just plain dangerous.

But do those big SUVs count?

urbanknight

Well that was my problem right there. I was more like 5m behind, and even that felt very close.

They're generally safer drivers than regular cars, plus they will take longer to stop, giving you a larger buffer than a small car that you would rear end before you even realized the brake light were on.

paul_858

You're dumb. Like Rasamatoo mentioned, you have to get stupid close to see any benefit of drafting. Consider just how close race cars (nascar/formula 1/ALMS/GT) have to get to gain the benefit of drafting.

At 2-3 car lengths, you're probably driving through disturbed air which is more likely to cause more drag than if you were say 10 car lengths behind the vehicle in front of you.

Wested

I'd much rather draft a big truck than a suburban or something. Think about it... do you really think a big 18 wheeler is going to be able to slam on its brakes and stop on a dime?

gregf83 

If you can't afford to drive please stay off the road.

cmh

But behind a semi (and sometimes SUVs) you are completely blind to what is going on in front of them. Behind a car you can still see the road ahead.

urbanknight

Corrected for cultural differences.

banerjek

It's a lot cheaper to pay for gas than it is to deal with damage to your car because you couldn't react to something the truck ran over. Add to that drastically increased likelihood of having a rock thrown into your winshield and the fact your ability to see threats from the front and sides is greatly reduced, it's not too tempting.

Drafting in cars is a really bad idea. If you want better mileage, get a high mileage car, drive it as little as possible, and go easy on the pedals.

urbanknight

Maybe that's the difference. Here in CA, 1/2 of all the cars on the road are SUVs. Besides, vision is extremely limited behind almost any car.

CastIron

Your insurance deductible is worth how much gas?

ShadowGray

They're safer drivers but then I really prefer not to fixate on the car in front of me. The best way to drive is to look over the car in front of you and scan traffic ahead... you can predict car movements much better that way.

I rarely use the brakes in traffic... usually if I see traffic stating to brake up ahead I just ease off the gas and by the time the guy in front of me is done braking I still haven't hit the brakes.

tinrobot

Just keep your tires filled and drive slower, it will save you a lot more gas.

dutret

your logic is faulty.

TRaffic Jammer

The issue isn't being able to stop but rather when the wheel assembly falls off the rig and it comes through your windshield, or a brake drum, hell we've seen whole axles on the side of the highway. Least that's the biggest up here in Canada. We don't even have those super takers on our highways up here, those things are insane!!

Johannes

https://action.publicbroadcasting.net...t/1001810.page

Dubbayoo

You, sir, are the idiot here. Drafting at a distance of 100 feet back @ 55mph fuel consumption decreases by 11%. 100 feet is roughly 5-6 full-size car lengths.


https://mythbusters-wiki.discovery.co...rafting?t=anon

TRaffic Jammer

55ft? Can't slingshot from that far back, get on your CB and ask permission to snuggle up. You want to be nice and close in the draft to really get it good. 5-6 cars lengths in Canada means they're are at least three cars in that space. Safe following distance isn't really thought much of here.

urbanknight

At that rate, you save 88 cents per hour of drafting.

Based on gas price of $4/gal in a vehicle that normally gets 27.5 miles per gallon.

CastIron

55 MPH is ~80feet per second. Your reactionary gap is incredibly small at 100 feet. Better to make one trip a week via bicycle.

munkyv22

I don't have to draft to get an aerodynamic advantage. It came free with the car.

Also, I don't trust other drivers enough to get anywhere near close enough to see draft benefits.

Doggus

Don't let Waterrockets see this. He has a bad case of the dump truck love. I hear he gets the cold sweats when he see's one.