My last "toy" was a '73 240z. Very nice car, and very fast, but died of frame rot over a decade ago.
The 1st gen RX7 is a very nice replacement. Not quite as refined, or comfortable, but lighter, quicker, and more race oriented.
I'm using 13x8 Revolution wheels along with 215/50/13 Sumitomo HTR 200s and I'm very happy with that setup. If you stay with 13" wheels, you keep a low gear ratio and lower center of gravity. But everybody has an opinion, and they will all be different. There's really no way to go wrong unless you try to stuff some 19s in there and still call it a race car.
