Because Kenne Bell superchargers are 20-80% larger in displacement (2.8, 3.6, 4.2) vs. the competition, they turn less rpm per psi boost and utilize larger pullies that provide more belt contact area and grip. Hence, less belt slippage. Also the lower power consumption / parasitic loss of the KB Twin Screw results in less engine HP to drive, thereby reducing belt friction.
Example: The standard 6 rib system is good to 15psi. The 8 rib system is recommended above (15-30psi).
See Boost Tables.
New front bracket, HD tensioner, pullies (alternator, water pump, idler (5) & tensioner), hardware and instructions. 6.6” Ford crank damper can be deducted if using the ATI overdrive.