This "black" tuning spring will change the stall of your Maxtorque clutch to 3100 rpm, perfect for a hot stock style engine where a moderate high stall is desired. At 3100 you won't damage anything but it will allow the engine to idle higher without lugging and still give you the kick off the line without being too crazy.

This is the stall speed we would typically run on LO206 racers, stage 2 ish builds and other fun fun back yard style toys