A junkyard car building game?
This was a flash game I played a really long time ago. I'm not sure what the title is, but I remember most of the game play. Basically you start off with a certain amount of money, buy junk like different wheels, different bodies, and different engines, and build a car out of that. Then you take your creation and start it off a ramp and land it on another ramp. You have to land it just right, because if you over/under shoot it, your car is totalled. The price of the wheels, and engine, give it more speed or something like that, but better bodies can sometimes add extra weight. I guess there could be variables in the vehicles such as speed, acceleration, and weight that could effect your jump. The controls are pretty simple with just and acceleration and brake button.

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