Re: Computer chip for 1990 200TQ

["POWELL, GLEN" <GPOWELL@rimail.interlan.com>]

          The IA method modifies the computer to accept higher than
          stock boost levels as "OK" without shutting down the fool
          delivery system. This allows the protection for over-boost
          to remain, although triggered at a much higher level.
          The IA mod also bumps up the timing (actually reduces the
          amount of retard as a function of boost) and also increases
          the rev limit cutoff point. One actually increases the boost
          (at least in older turbos) by installing a stiffer waste-
          gate spring and/or making the wastegate adjustable and
          cranking up the spring tension. I did both, made the
          wastegate externally adjustable (simple really) and
          installed a stiffer spring that allows about 10 PSI to
          17 PSI adjustable range. I'd like to find an even stiffer
          spring. I typically run at 15 PSI on the street all the time
          and the stiffer "green stripe" spring is very compressed by
          the adjuster at 15 PSI. I want an even stiffer spring so I
          don't have to crank up the tension so much. I think the AI
          mod also increases the timing advance when off boost.

          -glen