traildogg

k....whos got these and how much are they what brand is good what kind of performance increase is noticed if any, did you guys change the belts too mine are kind of noisy when you first start it in the morning, but seem to physically look ok...

fordf12002

you can pick them up at summit racing, jegs, any web site like that. you may see a little power gain but not much

mitchalvin

The power gain you see is due to the accessories spinning slower, this won't affect anything at speed but if you do a lot of low speed applications your battery can drain slowly.

andyman7931

this is the set that I got http://tinyurl.com/c25r5p

they seemed good, but the alternator pulley was a very tight fit. I had to clean the hole with sandpaper to get the paint off so it'd fit. I am not sure on performance yet since I never push my truck without the trailer behind it. The engine seems to run quieter with them on. The belt length is the same as stock, and installation time is a great time to put a new belt on. I'm setting my truck up to tow which will constantly rev the engine around 3k, so the slower accessory speed won't be an issue to me at all. I don't have hard data yet, but I guess that the gains from this are more than a k&n intake and the price is similar. For the price, I'm happy.

mitchalvin

If you keep the engine above 2K rpm you will not have any problem, my use tends to have long periods of time at an idle or just above idle while off road. I do not like to go fast off road due to the breakage that will occur so I am slow and in low.

Jamesb53191

i have a set from race parts in california. the alternator pulley didnt have a deep set like the stock so it wouldnt fit but other then that the kit went on easy. and if you have voltage problems set the idle set screw up a tad. thats what i did and it runs fine. goes between "n" and "o" of normal at idle. i noticed a power increase on my 5.0
im not sure the ratio but my crank is alot smaller my water pump was bigger and my alternator was the same.

i spent $40 ish plus shipping for mine

andyman7931

my alternator pulley was bigger, which makes for more electrical power at lower revs. It'd do more good with a smaller one, but I want to charge my trailer battery while driving so I'm happy my kit came with a bigger one. The most difference in speed is on the air pump and power steering.

Just call me Sean

iTrader: (1)

The larger the pulley the slower the accessory turns. That's why the accessory pulleys are larger, so they turn slower. That's also why the crank pulley is smaller, because it then spins faster to keep the accessories at a proper speed.

mitchalvin

The smaller crank pulley will slow down the accessories, think of a 15 speed bicycle the larger front (crank) gives you higher speeds, the smaller rear (accessories) will also give higher speed. If you switch to the smaller front and larger rear you have to pedal faster and end up going slower. This same ratio applies directly across to the pulley on your engine.

andyman7931

sorry guys... had it backwards... didn't think it all the way through. I'll be driving my truck today while loaded, we'll see how the smaller pulleys perform :-)