[2007 ion2]

So, like many of you probably have been doing, I've been paying attention to chevy and toyota, and how they have been allowing aerodynamics. Chevy seems to be focusing on the front end and panel gaps, and toyota seems to be focusing on a clean break of the laminar airflow on the sides of the bumper and a diffuser. Everyone seems to be using tire spats, more on that in a bit.

The car already has front and rear under trays, a relatively smooth bottom, filled panel gaps, filled door handle recesses.

The point of this thread is to discuss the next step for me, front deflector, tire spats, smooth wheels, and rear diffuser.

I studied the chevy line of cars, and the standard deflector height is roughly 6.25 inches across the board. I then walked over to the volt, and measured about half that height. My bumper sits over an inch higher than any of these. with the ride height compensated for, the volt (same car as the cruze, and very similar to mine) gives me a goal of a 2-4 inch deflector. At only about 3.5 inches from the ground, gm has omitted front tire spats from the volt. Thoughts?

Smooth wheel covers, sources?

Rear diffusers, there has to be some merit to this, since toyota is sticking them on everything not a large suv. Now, the number and size varies by vehicle size, but one thing I've noticed is they always tend to put them as far forward as possible with the camry having it's diffuser placed lower than the bumper, instead of at the same level like on the others. Thoughts on diffusers? Does the deflector limit the need for a diffuser?