underdrive pully

[kricket3000]

can someone explain what they do and the advantages of having them? kinda a noob question, i know

 

[AHHVTEC]

the pully makes the motor easier to work. and its a good bolt on its the only bolt on that gives true whp

 

[99sidude]

Unorthodox Racing sells lightweight ones. Before I went s/c I looked into them alot. They claim that the weight differance actually does more than the underdriving effect.

 

[kricket3000]

thanks for clearing that up for me

 

[norcalgsr]

Just to add the idea of the underdriving effect is that the pulleys are larger therefore requiring less effort for the engine to spin them because of a lower RPM..