I used EPI number WE435013, i used the weights they gave and the only change was i ordered the gold spring because the one they sent ingaged the clutch at a higher RPM and i wanted to hit the gas at a lower rpm.gas mileage its a pig anyways, but did'nt see a difference..Pull was much better..with the stock tires even with the Muddzillas it got out of its own way...<Muddie49
Just curious which clutch kit you purchased from EPI? I have a 2010 SP500 and want to "wake up" the performance a bit as well. Was there a significant increase in "pull" from the clutch change? Can you tell me which setup you are using, weights and springs etc? Lastly, and I apologize for all of the questions, did you notice any change in fuel economy?