Hey ive been contemplating whether or not to put a set of underdrive pully's on my 99 f150 with a 5.4 V8. my only concern is that i will have to also get a high output alternator (lots of money...). I know they make kits that say same charging characteristics but a friend of mine got a kit like that and his truck wouldnt stay running. So i was wondering if any of you have put underdrive pulleys on and whether or not you needed to replace the alternator, and whether or not they were worth it for that matter. Thanks guys

 

I got the two pulley set from JET, no problem at all with the alternator, steerring might me a little tough if you are turning the wheel while not moving, but once moving all is fine. The two pulleys in my set were the crank and water pump, and no problems with cooling either.

 

would you say that the power gains were significant enough to justify the costs? im not planning on keeping this truck a hole lot longer (graduating soon and am getting something newer as a grad. present) so i dont want to spend the money unless it is gonna be worth it ya know? And i also noticed that you have ford racign headers on your rig... i actually just got a set in for my truck and was wondering how big of a pain they were to install? looking at mine they look like theyre going to be a little frustrating... thanks again

 

If you are gonna be getting rid of your truck soon, then dont go with any under drive pulleys for now, but rather buy a set for your new year model truck, or car if you get that. UD pulleys do give back but not asphalt tearing by any means, but would be good if you are also gonna be coverting over to electric fans and removal of your factory clutch fan. Some on here have stated problems in the past with using underdrive pulleys but I have had mine on for over 4 months and all is well. Now, if you have a lot of electronics running at all times, even idle, and a standard alternator, you might want to consider upgrading your alternator first, especially if you notice excess drag on the motor now with lots of electronics running. If you dont have much more than what the truck came with, then I say you will be fine, you will just notice the steering a little sluggish at idle or very slow crawling speed.

As for the headers, yes, a big PITA!! They potentially could be a lot frustrating. IIRC, my installer had to loosen the engine/tranny assembly so he could rotate the engine around its crank axis to mount each header on the exhaust port bank. Another way would be to drop the front axle out of the way. Not easy but he got them on and they still look pretty under there. Headers were about $520 and $300 installed!! Yes, quite salty but as I tell folks, I had a $$$ gift from my folks so I splurged.

The installer was good, but he is more adapt to older carb engine cars rather than late-model electronic ignition trucks and that may have had something to do with the difficulty and labor charge. If you have an installer who has a specialty for late model Ford trucks then you might be better off than I was on install costs.

 

I got the 3 piece bbk kit and the alt. pulley was the same size, just aluminum. I would say go for it!