well, it's a good idea anyway.
I've seen far too many people want their daily driver to be a terror at the track and all they end up with is something that doesn't go as fast at the track as they'd like, and now it is crap to drive on the street.
Sadly both of my local tracks closed down this month.... doh! (they'll be back at some point)
If I wanted to make a cheap racecar, I'd probably just spend $1000 on a 70's F100.
Mine weights 3800lbs, and I could cut a ton out of it. Plenty of room under the hood, lottsa room for fat tires... parts are cheap, and if I put it in the wall, ohh well... it's a truck, there are still a hundred thousand more out there and plenty that are being parted out every day.