is any body can tell me that.

 

I think the TT in Greddy TT stands for twin turbo. Not sure about that but i know the TT is greddy's exhaust for forced induction vehicles and has wider piping to back it up. I believe the piping is 2.75 inch where as teh EVO2 is geared towards the naturally asirated buyer

 

^That, and the evoTT is also a true dual with titanium tips...where as the evo2 is a catback with...regular tips?

 

The EVO TT has bigger diameter piping for FI and is a true dual, the EVO2 is not a true dual and has smaller piping.