Hi all,
Time to jump in here. I've dealt with SWS chassis for years. The work is incredible and you can actually specify a few modifications and Justin will accommodate if he can.If you want to build modern sprint cars, this is the place to go. Unfortunately, you'll need some stuff Justin doesn't make. For wheels and tires, the place to go would be Big Donkey Resins. They make a bunch of different tires and wheels (sold separately, which I like) and, last time I looked an older KKR sprint body kit. For the other thingies you have to have, I would suggest engines and drive line components from any of the Monogram/Revell kits. Buy the cheapest ones you can find. The parts you'll need are almost exactly the same in all of them. Those kits were done in 1/24, but the parts should work with a little fiddling. The Parts Box (Australia) has some of the extras as well. Warning: all of the SWS, Big Dog and Parts Box products are resin. If you're not used to working with that stuff, it can be tricky.
Now for the SHAMELESS self-promotion. I make custom decals and I've made a bunch (I stopped counting) of sprint car decals . Whatever sprint car you want to build, if you can find photos, I can almost certainly make the decals. Just send me an email at gws.decals@verizon.net and we'll talk.
Anyhow, this info should help you build incredible sprint cars for either shelf or show.
Good luck,
Gary