so here's what i'm thinking, i was lookin into the march performance 10500 underdrive pulley kit cause it ups the hp and all the other good stuff. while looking at some of the past threads on here about underdrives i saw problems of charging, engine temp, power steering and everything else. so im thinking of what that if i underdrive almost every pulley up there on the engine it'll push out more hp. so will underdriving almost all the pulleys on the engine cause all the components on the belt to work like stock, but still free up the hp and tq or will it just not do anything to the power numbers?

 

You have to think what drives the pulleys. the drive pulley is the key to all of it. think of it as a bicycle. the bigger the gear, the less energy it takes to move, but more revolutions to move a certain distance. its the same concept. if you change the drive pulley to something bigger and keep everything else the same, everything is going to start performing poorly like you're hearing, but yet the engine will gain hp because of the less energy used to drive those components. if you underdrive every pulley, all the components will work(for lack of a better word) too much and you will actually lose hp because its taking too much energy to drive those ratios on every pulley. they make pretty good kits with good ratio's for our trucks. talk with ram_indy(i think thats his name). he has a good kit on his that he stands by from what i remember reading.

 

I recently installed a Hughes Engines underdrive pulley kits on my 01 5.2 . With the underdrive crank pulley it slows all accesories. Now I have not noticed any difference in my power steering or water temp(I run a 180 stat,so it runs cooler anyway). My Alternator gauge does drop at idle, and pops right back up as i accelerate, and stays steady at driving speeds.

If your running a big stereo,lots of lights,external electric accessories( ie a winch), the alternator drop may concern you. I really have none of those, but I am monitoring my battery to see if there is any significant loss of voltage or amps from the underdrive. Overall it was a very easy install for the pulleys, finding a proper serp belt,(the stock one WILL NOT work) wasa bit of a pain. Mainly because my local parts mass merchants gave me blank looks. I worked with my local parts jobber to get a proper belt.

Use the search feature,and look up underdrive pulleys,it should answer any questions you have.

 

I also put on the same kit. I have had no problems with power steering or water temp and I am still runing a 195. I have had it on for a while I can sit in traffic with my A/C on high and have never had a problem. Also never had a dead battery.