thinking out loud... again.

I've recently had an idea for a small sports racer heavily inspired by small bore, mid engine sports racers of the '50s and '60s. stuff like the Beach MK.4 or the Lotus 23b, sort of a cross between a DSR and a small GT car. for autocross, I'm guessing it would sit in either A-mod or B-mod, but where would I be at for roadracing, either with the SCCA or NASA (depending on whether they have classes for sports-prototypes or stuff like that)? I feel like a car like that would get slaughtered in DSR, and the inclusion of fenders sort of rules me out for any sort of junior formula class, and while a lot of GT-Lite/GT5 cars are pretty much a production car steel body sitting on a custom tube chassis (cue the GT5 minis and the '08 runoffs winning GT5/GTL car), from reading the GT class GCR, there are no provisions for garage-built small bore prototypes. I can't really find a place for what I'm thinking of. it would do just fine in vintage, except for the fact it would be a mostly original design from 2010, built in 2010 using parts available in 2010, not a vintage car, and thus not vintage legal. I figure I could probably find a class to stick the car in over in Europe or the UK, but that's not much help since I'm not in either place. I wouldn't normally be all that interested in roadracing, but for some reason I am, and if I'm going to be fabricating one car ground-up to autocross, that would mean i have the facilities to make my own stuff and thus I wouldn't really want to buy an existing car and chassis.

basically, is there a no-wings, small bore, GT/sports prototype class in the US, or was I just born a few decades too late for the race car ideas swimming around in my head?

In SCCA Regional classes there is SPU. You would be competing against Dwarf cas, Mini Grands etc.

would SPU work for a one-off design? I know that Baby Grands are homologated for SPU, but they are commercially available cars, not build-one-and-race-it-yourself-and-leave-the-rest-of-the-paddock-wondering-where-you-got-it. I don't know how homologation works for extremely limited production/one-off designs. also, is there any way to look up what local class turnouts are like, like a register of the number of cars per class per SCCA region?

Slyp, Go to the SCCA wesite scca.com. Go to the Club Racing tab, then to cars and rules for info on homologating. There are no specs for these cars in the Rule book since they are a regional only class. Try contacting DC Region SCCA also. They might be able to give you more info. I am pretty sure you can run a 1 off if it meets safety and displacement standards.