I was wondering how many people, after they did the Saab intercooler install, decided not to put the stock diverter valve back on. Yesterday I did it and decided to hear that it sounded like. I really liked the flutter sound. The only problem with that is that it spins my compressor the wrong way whenever I let off the gas.
Yeah, I'd put it back on if I were you. Your performance is going to be hurt without it. You've gotta wait longer to spool up after shifts. Also, I heard it's not good for the life of the turbo.