do pulleys actually free up that much power?

 

not "that" much.

 

Iv heard everywhere from 11whp to .5whp. Also keep in mind our cars use the cam to drive the water pump. Which means one less pully to benefit from with an underdrive swap.

 

Don't know for sure, but seems less drag equals better response. So negligible gains in power might still be accompanied by better rev response. jmho

 

if you search you will find the dyno before and after. The crank pulley itself only gained 2rwhp at peak but through the poweband it was a 6 or 7rwhp gain. So i would say its a real live 3-5rwhp gain over stock. Which isnt too bad for 100 bucks.

 

When I bought my car it had a underdrive pulley and I sold it real quick because the PS was hard at idle and the Alt barely put out enough current at idle.. IMO its not worth the hassle..

 

Peak HP gain = 0.7
Avg HP gain = 4.4

http://www.ws6.com/mod-2.htm