I closed the mouth on my Saturn, I moved it up with a nice contour on the belly pan. The yellow coroplast belly pan was brittle and cracked, so I replaced it with white. It should get better flow under the car. I'll test it on the foxhunt tonight. The vacuum line to the hot air intake valve got brittle and broke also, but with 90F temps I don't need it too much.
... Not enough air flow, engine temp kept creeping up on interstate. Opened it up some, now temp right around half way. Seems to be less wind noise and over speeds on down hill slopes.
I wonder if it would be better to have the air inlets open on the ends and closed in the middle. This would divert some air from around the front wheels.
I think the front looks much more aero.
I wonder if a metal plate as the bottom belly pan with cooling tubes soldered to it could replace the radiator.
Maybe taking off the insulation on the hood would reduce under hood temperatures.
was Before:
now, After:
Notice the aero licence plate holder:
