Aerocivic - how to drop your Cd from 0.31 to 0.17

[basjoos]

And the amazing thing is that I am getting these MPG gains while driving at normal highway speeds, unlike the turtle crawling speeds that drivers of stock Cd cars have to maintain to get comparable mpg's. Whenever I drive a normal car or truck, I feel like I am driving a handicapped vehicle since it starts feeling the air drag wall at such low speeds compared to mine.

[Darxus]

I think you might get gains by raising your car.

It looks like air that hits the nose has several times as far, vertically, to get over the top of the car as it would to get under it. And making air go farther out of its way than necessary = more drag. And it looks like not much air is currently getting under it.

[basjoos]

It probably would get better mileage with more ground clearance, but its not as easy to raise an independent suspension as it is a truck with solid axles. It would also raise the center of gravity and make it more tippy in a turn, reducing safety.

[3-Wheeler]

Originally Posted by basjoos

It probably would get better mileage with more ground clearance, but its not as easy to raise an independent suspension as it is a truck with solid axles. It would also raise the center of gravity and make it more tippy in a turn, reducing safety.

It would also expose more air to the tires, raising the air drag at that location.

Jim.

[basjoos]

I have fairings around my tires, so the drag increase would be minimal compared to the wind exposed tires found on most cars and would be compensated for by the reduction in underbelly drag. But in any event, the total reduction in drag would be fairly minimal.

[Christ]

Well, if you're interested, there are a couple ways to increase ride height on your ride... starting with those stupid hardware store "spring-helpers" which are nothing more than clamps that ride between the coils of your springs and keep them from collapsing. You can easily get an inch out of those.

[hendan]

Not beautiful, but WOW!

[The Toecutter]

basjoos, do you have any data on how the low drag has influenced acceleration above 60 mph?

I'm curious what your 60-100 mph acceleration time is.

[basjoos]

I've never timed the 60-100mph time(I'd be more interested in the 100 to 60mph time), but air drag doesn't become noticable until I get over 90mph, so the air drag isn't having much affect on slowing my acceleration until I'm up in the 90's. I haven't been over 92mph since I had the lean burn engine installed, but it is still in lean burn with a fair amount of headroom left when cruising at that speed.

[3-Wheeler]

Hi Mike,

Have you got any more mods planned for AeroCivic?

Your thread is one of my all time favorites at EcoModder.

Jim.