Well my tensioner pulley is whining it seems like so I was thinking about doing all of them. I've never done it to my truck and it's got 141k on it, I see a kit by BBK that says it "adds 8-15 HP"
Do pulleys really make a difference? Or should I just buy the tensioner and possibly idler?

 

Unless you have other mods (cold air, intake, exhaust) I would not mess with the pulley mod. Tensioner and idler defiantly though

 

I do have a cold air intake and exhaust from the y pipe back. But would do you think it'd make a difference?

 

Is there a mod for the stock tensioner and pulley to free up some ponies?

 

It will free up some just by eliminating the amount of parasitic drag, 5-12hp maybe. By the time it makes it to your rear wheels you probably won't notice but the engine won't be working as hard to spin the pulley's. Let me know how it works out, I didn't know they offered pulley kits

 

How would the drag be reduced? Better bearings? Lighter material?

 

going to underdrive pulleys are not really as sexy as you are thinking…

If you go here:
https://www.f150forum.com/f10/pulleys-128725/


You'll see that I said:
IMO, underdrive pulleys are an absolute waste of money … here's why…

because, yes, you take 2 lbs of rotating mass off the drive line but in the BIG PICTURE it's a drop-in-the-bucket. Think about what & how many more rotating objects are between the rubber on the road and the injectors…tires/wheels, brake rotors, axles, drive shaft, crank cases, transmission gears, crank shaft, rods & pistons, etc…

so in the big big big picture (also known as reality) you are reducing your rotating mass by a tiny percentage. The time & money is better spent in other areas.

 

UD pulleys will make a little difference along with an electric fan set up you will remove a lot from your rotating mass but you need to remember the pulleys slow the speed of your alternator and water pump so a larger output alternator might by needed, if you have a sound system in your truck you may not get the current output you need. As for bang for your buck, it's YOUR money, spend it how YOU want, once you've done the common intake, exhaust, programmer, you can get into E-fans, pulleys, throttle bodies, larger MAF but the results get less for the money spent, but that don't mean it's not worth doing

 

Its a piece to the puzzle, I wouldn't be so quick to throw it under the table...

Power steering alone is worth it. it gives you tighter steering response. I wouldn't want to slow my alt. down, because everythings electric, down to your fuel pumps, you don't want to start have crazy grimlins appear.

Waterpump also gets slown down and your motor might not cool as well, but thats not really much of a problem on our trucks.

I'm going with an '03-'04 Navi pump(aluminum housing and best perpeller design) on Cant Quits build and doing a rear mount radiator, also going to have 2 extra gallons of antifreeze, with aluminum tubing as the line. In doing so I'm going to need to slow down the waterpump to not be too cool.

 

cant put it any better way, mods work together, an exhaust or a CAI do very little on their own but add the two together and you have a difference you can notice, the UD pulleys do a little on there own but add E-fans and there's another difference you can notice, add a programmer to the mix with a few custom tunes and your making power... it all works together...

harley9703, any reason why you wouldn't use an electric water pump?