I've used the Caltracs, they do work. When racing, you need to preload the springs. When towing, you will need to unload the springs or you will bounce around. Right now I'm running lift bars by Superlift for traction. They keep the axle wrap down, but I don't hook up as well as I would like to. Although I doubt the stock suspension is going to work well with the kind of power we're making. I can pull a 1.76 60', but it still spins pretty bad. This is a 2WD on slicks.