If you watch videos of the super split and the speeco we have, it appears the super split runs slower. the speeco in original form runs scary fast as far as i am concerned. I have put the dr pulley on, and still don't run full throttle most of the time. I have been known to spray the clutch mechanism with wd-40 to allow it to slip more. Allowing the belt to "chirp" on occasion should also reduce your concerns about breaking the rack/pinion also, which is my biggest fear also, as I don't believe that can be replaced easily. Good luck.