Blower as in FI ? And if the FI doesnt touch belts why would it matter ? Yeah Im still kindaa noob to the FI stuff.

 

Noob Question:
Is there any negative effect that an underdrive pulley might have on our cars, like durability, reliability, and increased wear and tear?

 

They'll make your alternator, air conditioner compressor, power steering pump and water pump operate about 25% slower than their original speeds. If you have an aftermarket stereo system that increases the electrical load you might have a problem with the alternator not being able to keep up (more so at idle speeds).

Worst case scenario is UDP failure. It might not be common but it happens: https://mustangforums.com/m_4435611/tm.htm

 

I have used them on two cars. In both instances I have noticed a different. Was it night and day no. However, it was more of a difference is both cases then some mods that cost a lot more.