daveesrt6, Read OneHundered80's first post (page 12). The key information there is "Up to an engine speed of about 2900 rpm, the supercharger is actuated when engine load is more than 44%". SO, if you get to 44% load at 1200 rpm, or 1300 rpm, or 1500 rpm, etc.; that is when it will kick in. On a highly modified SRT6 (if you drive it conservatively) it is real easy to get to 2900 rpm before achieving 44% load. And with a highly modified SRT6, when it kicks in, it jumps, and is ready to blast off!