I did a test drive at 18%UD and I got 7 to 8 lbs of boost and on par for some boost charts.That is all the lower I can go with the pulleys I have so for now it will stay at that unless I cert my cage again,belts.I did a jet change to the intermediat cercuit but took some main jet out[2 sizes] and I need to put some main jet back in as the a/f was 14.5 to15/1 as my engine stall in the video will show and the engine was not very warm.