You might consider getting a good variable regulated power supply, that would allow you to dial back the voltage for cars that are too difficult to drive or crank it up for slow cars that are too stuck down. Gravity cars have no magnetic downforce, they are usually run at lower voltages, they can be expensive, and more difficult to find because they are made in limited numbers. There are actually two different Bulldog cars available, the first is the one that BRS Hobbies mentioned, the other is a gravity type car. With the neo traction magnet removed the X-Traction cars still have a little magnetic downforce, they do not want to slide much if you use good tires, but you may like them with the stock rubber tires. For now Wizzard only sells a bare chassis. The Dash cars can be bought as a complete car or a rolling chassis, you supply the body guide pin and body screws. Dash and Wizzard sell reproductions of the Aurora T-Jet chassis. The newest Auto World cars have neodymium traction magnets that would have to be removed.

The most commonly found ones are the Thunderjet 500 cars from Johnny Lightning and Auto World. Besides the original Aurora T-Jets there are plenty of clones available.

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