I just put in a new windshield, and before it was put in, I had the entire windshield tinted 35%, and put a 3 inch limo eyebrow
on the top, to off-set the color so it dosen't appear to be as dark as it is. Does anyone know if this hurts the performance of the radar detector detecting the signals? Don't want to waste the money if the performace is going to suffer. I have the older passport 4600, but have not used it because I don't want it messing up the tint. (only came with the windshield mount) Might end up buying a dashmat to velcro (if I buy anything) it down.

By the way, do not want to opt for the K-40.

 

It depends on if the tinting is silvered or not. If it is, you'll be severely decreasing the detection range.

 

Is it legal to tint the front windshield in Arizona? Here in TX we can only tint about four inches from the top...
I think it will affect it, if it has a mirror effect. Just like when you point a laser into a mirror, the laser bounces back..

 

If the tinting is silver, it will only affect the radar detection by a small amount. The more metal in the tint, the more deflection. But, it's only a very small amount. Your engine block and body block more than a thin film of silver tint could ever.

Laser detection on the other had can be affected more if the silver tint (or any tint) is blocking the detector.

However, the effect shouldn't be enough of a reason not to get a good detector if you feel you need one. My Escort 8500 (and my wife's 7500) on the passenger floor (read "behind the body and engine") can pick up radar signals almost as easily as when on the windshield.