Hi. By the models you listed i presume you're looking for a MKIV (JZA80). Great idea, i'm looking for one too!

I know for sure that the RZ is the factory twin turbo model. It comes in 6-speed manual or 4-speed auto. The SZ is the N/A model which comes 5-speed manual or 4-speed auto. Not 100% sure on the other models you listed but i think they are just varients with extras??? maybe but not sure. hopefully someone else might be able to help?

Depends on what sort of racing you're talking about. As far as power and possibility of maximum performance/modification, obviously turbo would be the way to go. As for transmission, for straight line drag racing i believe auto is the preferred/quicker option but as far as track work/drifting whatever the case may be, in my opinion manual would be bettter.

Hopefully others will put forward their opinions as i'm fairly new to this sort of thing but hopefully i have atleast helped get you on the right track for what suits your needs. Good luck with the searching.

Information needed
 

Hi I have recently decided to buy a Toyota Supra. I dont know much about the car yet but im trying to learn all i can. So if anyone has any helpful information to share it would be appreciated. Also I was wondering which type of Supra is the best as far as racing goes. Ive come accross RZ, RZ S, SZ, GZ, etc.