After have lots of problem keeping the DM1 on the ground while going over 90mph. I came up with an idea of sealing bottom of the car by making a cover with a pegboard. I guess you can say it's more like a borrowed idea from Traxxas' X0-1. I wanted to test out this concept before I make a better version of it. To make a long story short, it really works. The DM1 was a lot more stable at high speeds. I guess this mod it not too bad for an hours worth of work.
I put the car over the wooden pegboard and traced the chassis on to the board so I will know where to cut.
Afer a few rough cuts, here is what I came up with.
Test fit the cover on the car, and it seems to fits okay. The board is held on with 4 cable-ties on each arm of the car. Then I duct tape the board to the chassis and covered all the holes with painters tape
After a few runs, this is how it looks.
Here is a video of the car with the lower chassis cover. It was was not at full speed when it past the radar gun. I tried to do a second pass but hit a reflector on the ground and crashed.