basically you will need the ski w/wheels (a few have modded snow skis but I would not suggest it), an asphalt track (no lugs) which will get you on the track to see if you want to do more.
Two things to check is, find out if you have to run w/o coolant and use just water, we had to at Union Grove Wi/NSSR since we had no real overflow tank (at least that is how I remember it, may be different now) so we used straight water and a cool down unit that can be fabbed from basic parts. The other is a tether, newer sled have it but older ones didn't BUT it was one requirement.
The rest is all setup related,clutching, carbs, suspension. It really depends on how much you get into it. We got deep into it running the IHRA Summit series and was a big investment at least in respect to us, more so with time, but when overtime dried up my racing cash did as well. I can tell you it was fun and I do miss it and sometimes think about taking it out of the shed for a few runs...
