[MetroMPG]

I respectfully suggest your time & materials would be better spent on other parts of the car. As you say, the Echo's front end already has clean, attached flow with the OEM design. Outside of a wind tunnel, I just don't think it's possible to make an improvement with that kind of tweak.

I know that I would be disappointed if *I* put dozens of hours of work into a project and found no measurable benefit afterward! I generally try to avoid that kind of disappointment!