Tuesday, July 24, 2007

Hypermiling!

Because "driving like a granny" just doesn't sound as cool. So after a few months of commuting, I've found that no matter how fast you book it on the highway, it's going to take about 35 minutes each way if you're lucky. Since my wonderful wife got me an iPod for my birthday, I now have a reliable source of This American Lives and cell biology lectures from Berkeley.

So, why not take it to the other extreme and try to get the best gas mileage you can? The prerequisites are:
1) A stick shift.
2) A willingness to let it all go

I have the first, it took a while to attain the second, but last week I managed 38 MPG in my 2000 Civic with 106,000 miles. Not too shabby, I thought, especially since my drive is 7 miles of highway bookended by 6 miles of surface street on each end.

Like everything else, there are nutcases out there who give my newfound extreme sport a bad name - people who hit the offramp doing 50, shut the engine off, and don't touch the brakes until they hit the curb with their front tires at their destination. And people who refuse to accelerate at any more than a snail's pace - those lights don't last forever, and more than 3 cars would like to get through.

But, even being relatively courteous and relatively safe, you can do a lot. The biggest thing is the most boring - get on the highway, set the cruise control for 55 (if you're feeling mellow) or 60 (if you're in a frisky mood), and sit in the right hand lane. It's incredibly relaxing. In Atlanta, with 5 lanes of traffic to your left, it's like you're not even moving. I almost never have to touch anything from the time I get on the highway to the time I get off. For most cars, fuel economy tops out in 5th gear at 45 or so, remains pretty steady until about 60, then tails off badly - 20% lower at 70, 30% lower at 80, etc. And over 7 miles, the difference between 60 and 80 is nothing - especially since you end up braking and weaving trying to do 80.

Second - don't use your brakes. This just means, brake with the engine as much as possible, which forces you to drive with plenty of space in between you and the car in front of you. The ideal is that you never stop, you're always creeping up to lights until they change. In practice, this only works for me sometimes - like I said, the volume of traffic is usually such that if you creep too much, you're pissing people off who are trying to get through the same light you are. But, this morning, I made it through 4 lights without touching the brakes. This one leads to dangerous behavior - like cornering too fast to keep up your momentum. But hey - giving up speeding has to have some benefits...

Third - gentle on the accelerator. Duh. It takes real, Newton's-law kind of energy to accelerate a body at rest. In ideal world, it takes no energy to maintain the same velocity - in our world, you have to overcome friction and air resistance - but that's a lot less than accelerating. I try to shift at 2000 rpm now, and get into 5th gear as soon as possible (but without depressing the accelerator any more than necessary).

Fourth - maintain the car. I'm trying to do more of this on the Civic. (The van is big and scary, and I happily leave that to my Honda Dude). I look forward to changing or cleaning the plugs, air filter, and putting in lightweight oil.

Side benefits are, the car should last a lot longer, the drive is a lot more relaxing, and when you actually do have to accelerate, brake or maneuver, it's much more thrilling.

4 comments:

gashcrumb said...

Hey, that's funny, I've been driving like a bit lamer for awhile myself! Nothing like setting your cruise control to exactly 65 and watching traffic pass you by on both sides...

But at 3 bucks a gallon with a 60 mile commute I really could care less how many cars pass me by!

Ceridwen said...

The differences in gas mileage are even more pronounced when you drive something absurd. Like, say, a huge van. 60 mph = 15-16mpg. 65 = 8-11mpg. Yes, 8. Tasty.

Have fun with the maintenance. I changed the air filter once in the van. Since it requires wrestling with the doghouse, I haven't done it since. I'm sure it's easier with a car.

Iestyn Lewis said...

I don't think my Civic would have much luck pulling an RV, though, unless the RV was scaled for 12 inch action figures.

The air filter is a boy-racer one - you're supposed to squirt it with cleaner and oil it or something.

Sara said...

fascinating! Good to know there was a reason for my granny driving...