I have seen GN's at car shows for sale in the 10-15k range and they don't sell very fast. Our emission laws make post 1981 vehicles much harder to modify and that likely makes them not as desirable for those that want to race them.

Same thing with older 5.0 mustangs and Z-28's. Guys modify them to race them and then it fails the emissions test and they cancel your registration until you put the stock parts back on. My uncle picked up a used 90's 5.0 for a song after a kid put a Paxton blower on it and it wouldn't pass the smog test.