ok, so I put one of my legends together. I tried the rubber that came with the car, didn't like it much, but admittedly, I don't have much experience with rubber tires. Tried the car at 12volts and at 13.8. at either voltage I didn't like the rubber tires much. too much sliding around the corners. sliding around corners will not produce the fastest lap times.
Then I put on a set of quick slicks 43firm. it is as wide as the rubber that comes with the car, but it hangs over the skinny 7.38 mm wheel. I glued and trued them and then cut off the excess on either side of the wheel. so the tire is now as wide as the wheel.
I also added weight to the chassis. on 13.8 volts, I like how the 18,000 runs down the straight, but although the silicone gets better grip, with the controllers we use, its like a hair trigger, and if you are a bit too quick on the trigger exiting the corner, it can tip over, buy usually slides first.
at 12 volts, you lose some of the fun down the straights, but it was more controllable around the corners. probably because it was a bit slower around the corners. did not tip over one time.
the car is a bit too top heavy. I had the interior in the car, but not the other stuff like plastic engine, roll cage, front grill, windshield grill, etc. I didn't want to put that stuff on because I want to paint the body.
Cant wait for the Ford vs Ferrari series.