I changed the shoes at the end of each season. 4 black springs will get you closer to the engagement you need, or you can stack springs, 4 black springs on bottom and 4 white springs on top may get you close to 4000, can't remember for sure with the Fury since we always used 4 black springs mostly. I switched to the flame and it was the best shoe clutch I had seen, uses weights along with springs which allows you to fine tune the engagement even more than the fury. You can update your fury with flame shoes and weight kit easily