I've had a UR pulley in my car for years with no ill effects...I even swapped it over when I had the TII swap done. The only drawback is lower voltage at idle - I get full voltage with normal driving. For those with big stereos and/or other large additional electrical loads, I wouldn't recommend it. But, if the car has a good charging system and grounds, it's a good mod. The motor definitely revved more eagerly and there was a noticeable power increase.

An underdriven crank pulley aids in REDUCING water pump cavitation, no ill effects there either provided your cooling system is healthy.

Just another example of how mods should not be performed unless the car's main components are in good working order.

 

True True.......
the cooling at idle might need to be monitored a little more carfully, but the cooling while driving should be ok as you stated before it does "calm" down the flow, there for the cavitation in the water pump is greatly reduced.

 

Nope, untrue...with a cooling system in good working order (OEM fan w/working fan clutch, OEM thermostat, working) there should be NO cooling issues at idle.

 

"so if i was to take it to a dyno, would most likely people who work @ the dyno location be able to tune it?"

How many of these shops can tune an Rx7?.. I know for me I dont want to go to some jo blow and him charge 300 bucks to tune it wrong.