Since I’ve been driving, I’ve always had two drivers in me. The side that wants to feel the quick acceleration with my foot welded to the floor and the part of me that wants to maximize efficiency and get the best MPG. Over the years I’ve played with different hypermiling techniques and have noticed various degrees of success, some are impossible to do without pissing other drivers on the road and some are fairly easy to do without any other drivers even noticing.
For the past 2 years I’ve worked with a company that owns 3 company cars that my coworkers and I share pretty regularly. I’ve also noticed one obvious thing: I easily beat my coworkers average MPG by about 15 to 20% without even trying. While my fellow coworkers get low 30’s mpg on a 2013 Ford Focus with the powershift automatic, I tend to get close to 38 mpg repeatedly. I’ve even gotten into the 50’s before on a 60 mile freeway round trip*.
How to Hypermile without pissing off other drivers
I believe the #1 thing I do that gives me an advantage over other drivers is:
Take you’re foot off the accelerator as quick as possible!
If you see a light just turned red, or know it’s about to, take your foot off the accelerator right now! There’s no point in getting to the stop light 10 seconds quicker, you’re still going to stop. I hate doing full stops, I try to coast to the light and hope it turns green so I can hit the gas while I’m still going 10 mph. You’re car uses ZERO gas when it’s coasting in gear(as long as your RPM is above idle). This, by far, is the biggest place you gain your MPG. In low speed zones try to coast through as much as possible. There is so little air resistance at those speeds, you can actually coast for a fairly long time without losing much speed(or gas!). The one exception to this rule to be aware of who’s around you. If you come up to a stop light and notice a guy behind you is turning and trying to make the green arrow, don’t be a douche-bag, give a bit of gas and move over a bit to let him try to make it. That occasion comes up rare for me and even with that maneuver you’ll get better mileage.
Most people don’t notice or get irritated by it, although it might irritated yourself at first, I need to get to that stop sign NOW! not 5 seconds later!. Sometimes I think drivers in a hurry notice and incorrectly assume you are a slow driver. If they try to pass me I usually end up being the irritated one because they often drive slower than me on the open road.
My coworkers assume I drive like a 80 year old lady but I actually accelerate pretty quick and often ride the fast lanes on the freeway.
The common believe that accelerating fast = bad gas mileage is bull shit.
Yes, if you are at a stop light and slam your foot to the floor you will get bad gas mileage and yes, if you get your RPM’s get too high you will get worse gas mileage. The simple fact though is that accelerating too slowly can be bad for gas mileage too. You may have heard this before, the reason for this is your engine has a peak efficiency point of most power to fuel consumption ratio. This point for gasoline engines is usually around 3000 RPM. The other reason is at low acceleration your throttle body is mostly closed and this causes drag on your air intake, this decreases efficiency further. Lesson here is that it’s OK to accelerate decently fast up to around 3000 rpm then shift.
Driving slower, decrease weight, tires inflated and increase aerodynamics – the obvious advice to better MPG
Driving slower speeds increases MPG by 1) decreasing aerodynamic drag and 2) keeps your engine’s RPM’s lower(lower internal engine friction). I do occasionally drive a little slower when I’m not in hurry but I don’t go under the speed limit, especially if there are people behind me.
You can also lose weight by keeping garbage out of your car, some people go as far as taking seats and their spare tire out.
properly inflated tires reduce rolling resistance(friction) over deflated tires and will give you better gas mileage. Over inflating tires will decrease rolling resistance further yet but will come at a cost of uneven tire wear and shorter tire life.
The one Aerodynamic tip I was interested in trying is the small spoilers they put on the trunk lid of sedans. This works by creating turbulent, trapped high pressure air behind your car for following air to glide over. Same reason a golf ball has dimples and why trucks get better gas mileage with their tailgate up.
- Coast up a hill and accelerate down.
- Pulse and Glide – this technique was made for the Toyota Prius but tested well on the 2013 Ford Focus when I got over 50 MPG on a 60 mile round trip! That said this technique hasn’t seemed to make any difference on my Toyota Corolla or Saab 9-3
Why a 4 cylinder is more efficient than the same size 6 cylinder(or 8, etc.)
I just wanted to bring this up because I think it’s interesting. Let’s say we’re talking about a large 2.8 liter 4 cylinder vs a smaller 2.8 liter inline 6. The efficiency loss basically comes down to a few things(assuming engine design is the same).
- Engine weight increases with more pistons.
- Internal friction increases – think of the circumference length to surface area of the piston, as the piston size goes up, you have a greater area/circumference difference which you can think of as power/friction drag.
- More mass to move, this matters less at freeway speeds but can hurt your MPG around town.
There are pro’s to more cylinders like smoother power deliver but I’ll end my comments here.
*I did it out of boredom and used the pulse and glide technique for half the trip along with getting my foot off the gas as quick as possible. It was done without slowing anyone around me down. I haven’t noticed pulse and glide work on any other vehicle besides the Prius.