Originally Posted by GMCTRUCKS
I have those pulleys and what I did is I installed a high flow water pump and it does just fine even in this stop and go Texas heat im telling you the pump does really put out more water I seen the flow before and after.
I have no problem with underdrive pullies when they are used correctly, which in your case they are. My buddy has them on his gti and he gained like 5hp just from the crank pulley. If they work use them, but if you start having cooling, charging, or a/c problems then you know that you need to change something.