Air Dam Lip
 

Does a forward extending lip on an air dam do you any good? I'm working on a design that could go either way on this, but I am trying to weigh the benifits. I would like to keep most of the air from going under the vehicle, but I don't want to sacrifice any more aero that I have to. The dam is designed to be about half an inch lower than the lowest point behind it (front differential) and with a partial pan attached, should smooth the airflow that immediatly travels under the edge. After that, it's up to the skid plates to smooth out (with a few gap fillers where applicable) Bottom line is beyond the already flat nose of my vehicle, does a slightly extented lip do me good or harm?

dam
 

I think this would serve you well.Some of the highest mpg concept cars and highest performance super cars rely on reduced airflow underneath for both drag reduction and stability.Even when they have perfectly smooth underbellys.
Active-suspension is always involved to get it to the Nth-degree,but what you propose sounds good.
Journalists have reported,and authors have claimed,that therer ie a point of diminishing returns,as if the dam is sufficiently low,the added frontal area of it conspires to raise the drag back up.
If you can keep the air from colliding horizontally with the major bits and pieces hanging down,the air underneath will skim below with a clear shot to the rear.Wrapping the airdam around the sides is also beneficial,as you see today with NASCAR.

Luckily the front bumper I have now pushes the center of the nose out about two inches, but to clear the winch fairlead, I may push the center of the airdam out another 1.5 inches or so, and mount it to the bottom brackets of the bumper. The wings of the airdam would however sweep back to the edge of the bumper and completely shield the tires, hopefully allowing the air to flow around the fenderwells and on back relatively smoothly. Again "hopefully" making a "pointier" punch through the air!

You can see what I did with my air dam... :D

sorry, the crappy filtered internet that I'm on isn't letting me see the pictures :(

The air dam on a T-100 is basically flat...so I dropped the air dam 6.5" and pushed out the middle section of the air dam about 3.5". Not sure it's doing any better...it's only been a few weeks. ;)

Then I put in a brace bar in the back and attached some coroplast to button up the bottom fer a cleaner flow. :D

BamZipPow -

Ingenious execution! I love them thar shelf brackets.

CarloSW2

Round bottom edge for low drag, splitter for maximum downforce.