Our stage 2 upgrade for the supercharged Lexus iS200 is based around an increase in boost pressure.

The way this is done on a supercharged car is to increase the speed of the supercharger by changing it’s drive ratio.

The standard TTE supercharger system normally produces 1.35bar of boost pressure (absolute). Our stage 1 boost upgrade pulley kit produces 1.5 bar (absolute), and our stage 2 boost upgrade kit produces 1.7 bar (absolute).

Here is a picture of the stage 1 and stage 2 pulleys for comparison purposes

Here’s a picture of our stage 2 boost upgrade pulley kit (including belt)