I have a 93rx7, a local shop told me that they could make the turbos squential i think, where both turbos stay on and not just one then my 2nd turbo come on. They also told me to get a fuel controller like a apex-i one. Has anyone done this to their cars, how reliable is this, and how much faster will this make my car. The shop also told me it would cost around $200 to do this to the car. thanks

 

Try doing a search(top right corner of the screen) on "non-sequential turbos". I'm sure you'll find plenty of info there.