i have had them on EVERY stang I have ever had. 1 V-6 car / 3 5.0 cars / 5 4.6GT's / and 2 4 valve 4.6 Cobras and I have NEVER had a problem with them other than the alt pulley not charging enough for a big stereo. They are a good way to " free " up about 10hp for a low price. They average about 100 bucks....some a little more just depends on where you get them from. I would suggest them for a nice bolt-on.
O0 I second that. I just put a set on this past weekend. So far, engine runs like it did, except with a little extra oomph. Cheap, quick, easy way to get some extra ponies.
I put some on mine, only downside [i'm sure everyone knows] as the alternator is going pretty slow at tickover, if your out at night and sitting still, its best to put it in neutral, if you sit in drive, the voltage drops and the lights can dim quite a bit. No problems in the day though.
Well I got a stereo and its fine but at a stop light my voltage does drop down low, and I know its as a result of adding underdrive pulleys, I run a optimia battery and a 170amp alt. A capacitor should help me though.
Some company sells an OVER drive pulley for the alt. I compensates for the other 2 small pullies and doesn't give you charging problems. I've never used it but I was told it worked. Try leaving the stocker on as well, that was also said to work.
underdrives alone dropped my e.t.'s .15 in the 1/4......but yeah the voltage drops considerably at idle
I will not run a UDP for a 4V. The potential for the damage they cause isn't worth the 10 hp for me. They have been known to cause oil pum gear failure being the balancers aren't that great and have chewed up some gears and caused engine failures. Al Papito wont run them unless he has an ATI Dampner along with others. However atleast 9 motors have gone to the sh!tter because of them and Bob Cosby's motor was damaged but luckily he had billett oil pump gears which saved him.
I have heard about that too, but from everything I have read that is caused by IMPROPER INSTALLATION, and NOTHING ELSE.
MARCH PULLIES!!!!! Their craftsman ship is beautiful, I got the polished and I got a little wood when I opened the box for the first time! Install was easy and I felt a SOTP feel from them.