I am recently a new ownwer of a Honda Civic and was considering lowering my ride height a little for looks and better MPG. I don't want to slam it to the ground since the roads around here are rough and I don't want to scrape it. I've read that it will lower MPG's but by how much?

 

Nothing notable if anything. I can see that being true if you don't get the car aligned where the tires will essentially be "fighting" each other from the toe changes. An alignment will fix that.

If you have toe issues that are not corrected, you will be going through tires like once a year easily.

 

Yes I am aware of the change in wheel alignment when height is altered. I've always worked on 4x4 trucks and I know that when you get just a 2 inch leveling kit to raise the front end, it effects the MPG by at least 2 MPG. I didn't know if the MPG's were effected on cars as much as trucks.

 

Any news on this topic? I'm pretty interested. I use a bit bigger wheels on my civic, which raised the car by about 10mm. My mpg dropped, but it is because now the distance I drive is measured incorrectly: wheel girth increased about 3% => distance I drive is 3% more than my clock says.

 

that is not true. a leveling kit or a lift kit for that matter will not affect MPGs on a 4x4 vehicle. the tire size, alignment, air pressure, and toe/camber is what will. i also know lowering a truck will not affect it either only the mentioned variables will. therefore i wouldnt see how lowering a car will affect mpgs unless (as stated) the alignment is off or if the tire size is changed.

 

That's not true at all.

 

You're not changing the aerodynamics of the car since all you are doing is lowering it a bit. Lower it + a significant change in aero throughout the car and you MIGHT see TINY difference.

But simple answer, no, it won't lower MPG's.