As those who saw my first post (
http://www.gassavers.org/showthread.php?t=2708) know, I did some aero mods to my car before coming here and was less than impressed with my initial results. You can see in my vehicles fuel log that I got no real improvement out of my first attempt at a grille block and underpan. My instant MPG was higher at some points of my drive but overall not much changed. I've put some pics up here:
http://rides.webshots.com/album/557657592RszklZ
I was even further disappointed when I left the bellypan off after doing an oil change (ran out of time on the weekend). I decided to try an informal A-B test at that point so removed the grille block as well and put the stock air dam back on. On my in-dash MPG readout I noticed no difference except on one stretch of my drive, and my mpg at the pump was the same.
I'm not entirely sure at this point what I did wrong with the first setup, but I decided to try again with grille block v2.0. Doing this during the week, a grille block was all I had time for. This time I put the grille block on the outside and went for total blockage of the upper grille while leaving the lower open.
After just one day with it on, I am calling this one a tentative success. Even with only the block I have seen FE gains on my dash readout throughout my commute. I was very impressed when I saw gains of several mpg in places where I had not seen a difference between my first mods and stock. So, it seems that the placement of the blocker matters alot more than I first thought.
So, now I am looking for ideas on where to go next.
I still want to work on the underside, but what was wrong with my first bellypan design? The frontal area was no different than with the air dam and I thought for sure that it would be cleaner for the airflow. I do intend to include wheel spoilers on my second bellypan though.
Or would it be just as/nearly as effective to just extend the stock airdam out to the sides and incorporate it into the bottom of the wheel spoilers but leave the engine bay open? (you can see the stock air dam in the photo of the second grille block)
I also want to try sealing in the area between the spare tire well and the rear bumper cover. It's like a big scoop back there and I have noticed dirt and gravel
collects up there, so it's gotta be trapping some air.
Another idea of mine is to add a hood vent (a'la GT-40, but in minature) to let underhood air fill in the low pressure area at the front of the hood and shift a bit more of the airflow to over the car instead of under it.
Of course, there's always wheel skirts. It's a Chrysler sedan, so they're right in character!
Could probably work some kind of gap filler in the front wheelwells.
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