Im not sure if Im using this term correctly, but what is underdriving as pertaining to the aftermarket pulleys. Will this damage the engine or A/C? thanks.

 

smaller crank pulley = less rotational velocity = lower belt speed = slow rotational velocity of accessory pullies = less power generated for accessories.

won't damage accessories

damage to engine has been discussed 10000000000 times, no evidence to support it as of yet -- use the search function for more info

 

mild underdriving of the accessories will cause no harm. Most aftermarket pulleys, like the popular UR pulleys, underdrive by 15%, but most of the gains come from the lower rotational mass.

 

So instead of saying it will damage something, maybe its better to ask how will it affect say the output of the a/c and other things?

 

i haven't noticed much of a difference (i have the U/R pulleys), and I have had the 2kW stereo, nav, AC, high-speed wipers, and headlights on simultaneously... didn't try high-beams, but i don't know how much more they take than the standard HIDs.

 

You wont notice anything at idle. As soon as you rev it, the compressor and everything else are essentially maxed out.

My AC blows just as strong, and my voltage is perfect.

 

Oh, I thought "underdriving" was when someone couldn't drive their car to its fullest potential.

 

Underdriving is batman's special driving position when he's really focusing on driving.