Replace your stock diameter crank pulley with this Power Pulley from EMPI. This aluminum 5-hole design pulley is smaller than the original crank pulley and has black timing marks. On a stock set up, the crank pulley is larger than the generator pulley, so the fans spins more than once for every rotation of the crank. A smaller diameter crank pulley (or power pulley as it is sometimes known) changes the ratio between the two, effectively reducing fan RPM relative to engine rotation speed. This minimizes the load coming from the generator fan and frees up engine horsepower to be used to move the car. Installing a power pulley will reduce engine cooling and charging by the generator. This power pulley fits on all 12 volt Type 1 VW motors, including 1967 to 1977 Standard Beetle, 1971 to 1979 Super Beetle, 1967 to 1974 Karmann Ghia, and 1967 to 1971 Bus.
The outer diameter of this pulley is roughly 5 13/16"/148mm. Coupled with a standard upper pulley with an outer diameter of 4.25"/108mm
the pulley ratio would be approximately 1 to 1.37, meaning the fan will turn 1.37 times every time the cranks makes one full
revolution which is less than the factory ratio of 1.69. This means the pulley won't cool as effectively as the stock unit but does
use less power to turn the fan which frees up horsepower.
California Prop 65 Warning:
Please Note:The information listed below is for stock, unmodified VW's manufactured for sale in the US. VW's are commonly modified and very often parts from another year VW may have been installed on your car. California Pacific JBugs is not responsible for any errors if your car has been modified in any way.