Although they are similar systems, Indy (California) uses EMVs (enhanced motion vehicles) which are on hydralics so the car can bounce, bank, climb, whatever on straight track. JTTCOTE cars do not move at all and follow the track, and is much more similar (identical system) to Test Track then Indy.
Now that the Studios have a imo better stunt show, Indy is obsolete, and more of a C-Ticket (in terms of whether you have to see it). I'm much rather have an Indiana Jones and the Blah of Blah.