Just wondering if there is any cons to underdrive pulleys. I have them on my 91gt and my battery gauge is always on red at idle, but then when its driving its fine. If this is the same on the cobras then i probably wont get them. I know for a fact that they help the engine rev a little more freely. Cause i felt a difference in my 91. Please advise.

 

No disadvantges, get em.

 

I have had problems with the alternator not getting a full charge while at idle on two of the mustangs that I have had them on. One was a 94 GT and the other a 97 Cobra... I can't recall what brand they were, and not sure that it really matters as far as that problem is concerned, but there isn't anything wrong with installing them without the alternator pulley... Doesn't really make much a difference...

 

it lightens the load on the motor to power the accesories, it does make a slight difference and has nothing to do with the alternator charging, that was just something done wrong as far as i know.

 

I had them on my GT and they add more throttle response and supposedly gives better gas mileage.

 

so get em. No disadvantages