Taller front tires to reduce windshield angle
 

So I was thinking about running a larger set of wheels/tires in the front of my car to help reduce the windshield angle. What do you think?

Eh, miniscule difference, i'd say. Not to mention silly looking, potentially unsafe, your speedo would be way off and you would introduce a ton more air under the car.

Well you'd be reducing the windshield angle, but anything you gain will be lost on the underside

Lowering springs in the rear. Strut cap spacers up front. Alignment. Front bumper via Nascar styling department.

Do it!

What is the current attitude of the car? Does it sit lower in the front? Do you have an undertray installed?

Hucho did some tests on windshield-to-hood angle, and found that a more obtuse angle was better, but the effect was small. But you're proposing to change roof and underbody angle, and the amount of tire exposed to the air, all of which will have a bigger impact than absolute windshield angle.

seems to me you would increase the frontal area by making the angle of the floor anything but parallel to the ground.

I too was thinking that the underside exposure would be a problem. I might try this in the future anyway as I do plan to get 13 inch wheels after my current 12s are all worn out.

I agree with RobertSmalls. You'll likely gain in that one area, but loose in a lot of others.

Also, the rear window (if it's a sedan) would be steeper