Your answer is false ... you can turbo both the GT and the GTS .. it all depends on how much money you want to spend.
GT is good for about 10psi , 7psi safely ... GTS I have no clue
GTS has a high compression ratio so it is not a good canidiate for forced induction, i.e. turboing.
GT is better for a turbo.
There are turbo out for both the GT and the GTS.
Please search the forum using the search function ... keyword "turbo" this topic has been covered lots and lots of time ... you should find plenty of information to answer all your questions.