Under drive pullys or no?

it seems that it is hit or miss for many. some guys curse them and ditch them and others love them. has a lot to do with the car and its componentry. they can be marginal with a stock idle setting (652 rpm).

my two cents. good luck (if they are real cheap get 'em and try 'em - you can always swap back and not be out much $$).
 
i just put them on my car and i also have over 1000 watts of thump and i dont have any problems. i didnt use the alt pulley though just to ensure that i would not have any starting problems. No cooling problems and car seems to run much smoother and revs cleaner and a little quicker. i say get em
 
My alternator was not charging at idle with the set of mac pulleys.<

It did not cause me trouble cause at the minute you touch the gas pedal the charge come back.


Just to have a constant charging alternator.I did put back the stock alternator pulley and i left the water pump and crank mac pulleys.
 
First of all, for all that do, I generally wouldn't blame charging issues solely on under drive pulleys. The dinky little externally cooled 75A alternator that Ford put in there from the factory sucked to begin with. Even before I had the pulleys, the gauge always read below 12V at idle. If you’ve got cooling issues with them, then I’d start addressing other areas of your cooling system before I trashed the pulleys. Because the little bit that they slow your water pump down doesn’t cause your engine to heat up all that much…..even in warm weather. Pulleys are by far the best bang for the buck mod you can do. They cost next to nothing and are the only mod that will actually improve your fuel economy rather than hurt it. That is....unless you tend to drive with your foot in the oil pan all of the time. ;)

For the record, I run Mac under drives, a big stereo, my car has air and was converted to an electric fan.

NO CHARGING OR COOLING ISSUES, WHAT SO EVER!!!
 
I never had a problem with my pulleys stock or moddified. I've been driving with them for over six years now. They do cause the alt to charge a little less but that never drained my battery. Car cooled just fine too.