Originally Posted by
kb525
Ive done some small work with underbody mods on my f104w. Pics are somewhere in this thread, click my name and scroll through my posts to find them. I didnt seal the entire car like you did but did seal the rear pod with skirts and a front diffuser in the front wing. The front diffuser proved how good the idea was as the car was being much too loose in corners to the point i couldnt go flat out. I removed it and with noother changes the car wouldnt turn at all. I then put it back on and again too much oversteer. Went home and added the rear skirts and the car was understeery again but not to the same as before. Tightened the center screw and i could take that turn flat out all night long
As someone said heat started to be an issue. Solved by opening the engine intake at the top
years ago I was reading aero information for oval cars on velodrome tracks. A website had built their own windtunnel and was able to test bodies for front and rear downforce and drag. They tried sealing the body off, keeping the rear bumper in, and other tricks. They found that keeping it sealed up not only improved drag, but downforce as well. Smoothing the flow created a low air pressure area under the car and helped it stay on track. The did decide to continue to cut out the rear bumper, because it helped maintain stability on the large tracks. This was all backed up with laptimes as well.