We use dirt, so its easy to "fix" a jump if it seems to "fling" the cars rather than fly them. The primary trick, is NOT too much curve. The thing will go nose up, and never land right. You want to base the height and angle on how high and far you want the car to fly. Best way to figure it out, is experiment. Take a piece of the material you plan to use, and prop it up in position. Run the RC at the speed it will hit the ramp, and test it. You might need to raise or lower it. I suggest you only use a curved face if you want lots of altitude. If you want the RCs to jump low and fast, use a straight/flat ramp face.
