Looking at maybe getting some underdrive pullies for my truck but can not justify paying over $200 for them. Was looking at the Motoblue pullies from RPM Outlet but they are not available.

So I know the mustang ones fit on our trucks and are cheaper but which ones...I have been searching for about an hour and havent found someone actually come out and say which years fit. So if anyone could enlighten me, it would be greatly appreciated. Also if you know of where I can purchase them. Thanks

 

this may be a dumb question but what is the purpose of underdrive pullies?

 

its slows down the accessories run by your belt...ie. water pump alternator etc. By turning these accessories slower it frees up alittle horse power. Many have claimed a small increase and better throttle response. Its not recommended to under drive your alternator, it causes lights to dim and may have problems keeping the battery charged. Most swap out the harmonic balancer and and the water pump pulley

 

Intresting I think I may do this

 

I have dine these on all my vehicles....Very recommended IMHO.
I like the outcome they give, a tad better "get-up-and-go" and a little better mpg's.

Look at SteedaTrucks.com I think they have them on the site the ones your need.

 

Beware if your running allot of aftermarket audio...

But yes they do help... But do have side effects...

 

Such as?

 

^ If your turn your alt. slower, then your not cranking out as many amps. If you over pull your alt. then you will burn it up.

 

Thats why most ppl dont get the alt pullies like they used to...now many just swap out the crank and the water pump pullies.

 

wont having a smaller crank pully cause the alt to turn slower?

 

Yep.

 

That's why you take your programmer and up your rpms about 100 rpms.

 

Anybody know which Mustang UDP's fit the 5.4?

 

bump

 

I found out its the 2005-2010 4.6L motors.