6821 - 21" Short Belt - Crank pulley to Fan pulley - 78 to 86 16v & 32v

Crank pulley to Fan pulley - 78 to 86 16v & 32v
Porsche used two different pulley diameters #10, so to ensure you have the right size belt, measure the outside diameter of the pulley #10 that drives the fan. 106mm pulley will need a 21" belt. 86mm diameter means you need a 20" belt (6820).
Smog/Air Pump Removal - this belt is used to drive the fan pulley directly from the crank pulley. This belt is installed by removing the three bolts that hold the fan pulley bracket #1 to the block. Allowing the bracket #1 to fall forwards, fitting the belt, and by tightening the bracket back to the block, the belt achieves perfect tension.