RabidStreetRacer

iTrader: (1)

I ahve been hearing about people putting "underdrive?" pullies on the 5.3. How much does that help in power wise and who makes some good ones for our truck? Will i lose any reliability on my a/c and alternator?

1ImperialSS

iTrader: (5)

ASP makes some good ones, helps with about 9hp on our motors, if you get hte package with the UD pulley and smaller alt pulley it wont hurt your alternator too bad as far as output. they usualy run 225 from summit but make sure you get the one for the 5.3 not the 5.7 because your serpentine wont line up correctly

erronisme

what about loosing the A/C at idle?

1ImperialSS

iTrader: (5)

it will not be as cold i think but not too much and i think it would be well worth it. i mean, you dont idle THAT much

blake2kz71

iTrader: (17)

I have a diamond sub & diamond 600.1 amp, in-dash tv, and playstation in my truck, would the alternator pulley kill all this stuff while idling?

SnakeOiler

iTrader: (6)

It didn't change my a/c one bit

Get the underdrive alternator pulley. that's what I did - stays right at 14volts

LS1TRUCKGUY

iTrader: (7)

with your stereo equiptment, i would get the alt. pulley. with my headlights and ac on, it pulls down to 12 volts @ idle. it would be much worse with your stereo...... my a/c did not change at all........