Interesting thread..... I feel at home already!!!
For those looking for shells, especially some of the older Carson bodies, TeamBlueGroove are now remanufacturing certain ones.... like
this Audi Sport Quattro S1... not sure how it will hold up to rallycross conditions, but could be good for an option.
Plenty of chassis' that could be used here.... Tamiya with TA01/2, M03 rally-converted or M05RA, DF03-RA, there's plenty of options. Outside Tamiya, there's models like the Schumacher SST Rally, Kyosho Alpha, HPI RS4 Rally, Losi Rally Weapon, just to name a few - plenty more as mentioned by others.
Best to keep it with the 190 - 200mm jobbies, perhaps.... if you start allowing me to bring my Kyosho Celica, it may push those fragile Tamiyas about....
lol....
Good luck with the class! I'll be watching....
Alex