using underdrives and the stock alternator is asking for trouble. throw on a 3g alternator and the pullies and problems solved. i have this setup on mine and i can run the heater at full wipers on, headlights on and have no problems at all. hell the original alternator wasent even good enough with stock pullies. it would dim the lights when i had everything on.

 

when it comes to UD pulleys they are all the same and they are all worthless

 

not to mention the cooling problems you may have if you have another underlying issue. charging issues with stock alt. you should upgrade to a 3g alt anyways having a sound system and all.

only one that might be worth your while is the crank...but again not worth the cost. im getting one cause i can get it super cheap.

 

alright i'm liking the arguments hear, most definitely gonna put the money to some new headlights. and a strut tower brace maybe. true its not worth the charging issues and the 4hp increase

 

Another option still: Get the underdrive pulley system with the amp kit. It allows the alternator to spin faster to make up for the idle problem. I've done it and was happy with mine. Asp Racing has a kit Part No.: ASP520124 that you should be happy with.

The only problem is removing the alternator nut if you ever want to change the alternator pulley back since there is not sufficient wrench clearance with the pulley being so small. Naturally in the summer you will notice a reduced output from the AC at idle.

http://www.aspracing.com/ford.htm

 

I have a PA Performance 200amp 3G alternator. I was using an aluminum BBK UDP set and the system wouldn't charge at idle. I have no sound system but i do run a set of dual electric fans. I put the PA Performance alternator pulley back on and it still wouldn't charge. I put the stock crank pulley back on and now it's charging. The BBK water pump pulley is the only one still on the car. I am running a FRPP smog delete pulley and still have power steering and AC. That way if i ever shred a belt on a road trip, i can stop at just about any auto parts store and pick up a stock size belt. I am curious though, if i ran a shorter belt and got rid of the smog delete pulley if it would work witht the UDP's. Anyone with any experience. I still doubt i'd do it. Just doesn't seem worth it.

 

7 yrs w/ the March Power and Amp UD and I've never had a cooling or charging issue.
Yes; I'm still using the Original Alt and Water Pump that came on the car 186K ago.

 

For what it's worth..... I broke my belt the other day due to a locked up AC compressor... While I was driving the car a few blocks back to my house with no belt I decided to punch it a few times since it my temp wasnt getting to high...


I felt no difference in performance what so ever.... and this was with no belt at all. I'd been thinking about underdrive pulleys but now cant imagine noticing any gains with them.....

 

you're the exception. lol! your car is so clean that i doubt you have an grounding issues/insufficient grounds. no resistance issues. and i bet your cooling system is cleaner than a post colon cleansing patient.

 

Alls I know is, I'd much rather spend the money on other items than on UDP's. I wouldn't even have them if they hadn't come on the car when I bought it. And unless you've done everything you possibly want to your motor and just want to squeeze that tiny little bit left from it, totally go with the new light housings. I love the look of an awesome housing, and it adds so much more prestige/awesomeness than dimming interior/exterior lights.