Just got my BBK underdrive pullies(pics inside)

[daveshapellSVT]

I got my BBK underdrive pullies today and i installed them.. just posting so if anyone has questions about them.. They are fairly easy to install.. I did it in my garage with one trip to a local shop for air gun usage for the alternator pulley.. Only thing that gave me a problem was the crank pulley, which required a pulley puller which cost $23.00 at advanced auto.. Along with that i had to remove the fan to make enough room to fit the pulley remover.. Not that hard, i just didn't expect to do it. Only thing that bothers me is i'm left with some parts from the kit.. i'm thinking they are just universal parts perhaps used on another motor.. there was nothing they could be used for in this application..



Anyhow, i love the pullies... There is a noticable defferance just in driving it after the install.. i recommend them...

[j302]

are they easy to install? does bbk sell ac eliminaters as well?

[daveshapellSVT]

they are very easy, and i do believe BBK makes an elimintator... where are you located? perhaps if you are close and need help i could help out...

[Ace$nyper]

sweet looking and sounds like it was good upgrade!

[HiFlow5 0]

Look, you even got the "tool" you used in the pic!



LOL. Just messing with ya dude!

[daveshapellSVT]

u jerk lol... it's all good dogg.. i get so happy when i get parts i just wanna share with everyone.. plus theres some questions ppl have that i could help them with now that i have installed them and know how good they are in the car..

[SIKCRX]

you look like that guy from friends lol

[SikNingStang]

you can help me... send me some money so I can get some. lol... they look good

[SikNingStang]

oh yea I meant to ask... do you have to change belt sizes when you get underdrive pullies?

[daveshapellSVT]

Not with the set i got.. I have the set with the crank, alternator and water pump.. they are all different size pullies from stock, but it just works out that you can use the stock belt.. However i recommend getting a new belt.. My stock belt was warn and shitty so it sqeeked after i installed the pullies.. i went to auto parts and got a new one that was better than stock with horizontal metal lines in it.. cost me 30 bucks.. the stock replacment was 16 so i figured it was worth it.. Swapped it in like 5 seconds and the sqeeking went away and the belt was much tighter also.. it's so easy to change the belt, you just push down on the tentioner and wiggle the belt off the alternator pulley.. mustangworld.com has a section that talks about underdrive pullies and how to install them and what they do.. theres also a diagram of the engine and pulley set up..

UNDERDRIVE PULLEYS

Notice the diagram above. Each accessory on your engine has a "pulley" on it. The pulley is the wheel that is mounted on each accessory. Your engine has several accessories. Alternator, water pump (pulley with fan attached on 5.0 stangs), power steering pump, air conditioning compressor, and a possible air pump (5.0), or supercharger. There are also several idler wheels that are in place to put tension on the belt so it won't slip. There is a spring inside the belt tensioner that holds these idler wheels tight against your engines accessory belt (often referred to as the "fan belt" in the past). The crank pulley is driven by the crank shaft inside your engine. It is the pulley that "drives" or turns all the other accessory pulleys in your engine.

As you can see, the stock crank pulley (above) is rather large. By using a SMALLER pulley for the crank, we can reduce the amount of horsepower used to turn the other engine accessories. A smaller crank pulley has more leverage to turn the other accessory pulleys. We can also further reduce the amount of horsepower used to turn accessories by INCREASING the size of some other accessory pulleys in our engine. The most common accessories chosen for these larger pulleys are the Alternator and Water pump. These larger pulleys are referred to as "underdrive" pulleys, because of their larger size, they will rotate less frequently, hence the name "underdrive" pulleys. If we only had a smaller crank pulley in place, we would need to get a new belt, the stock belt would be too long, by using larger pulleys on the alternator and water pump WITH this new smaller crank pulley, we can retain the stock belt.

After looking at all this you may ask " hey, does it take that much power to turn the alternator and other accessories ? ". Yes, it does, if you ever tried turning a stock alternator under load, you almost can't with your bare hands. As much as 10-20HP is used up by accessories, but there are some accessories that we can't do without, like: alternator, power steering and water pump. If you are willing to do without power steering and air conditioning you can gain even more power. With everything in place, you can expect a 5 HP gain on a stock Mustang by using underdrive pulleys.

Keep in mind, because you are now "underdriving" your alternator, you will need to make sure you rev your engine above a certain RPM (depending on the alternator underdrive pulley) to like 750 or 900 RPM before your battery starts to receive a full charge. This means that at idle on a stock Mustang, your battery may not be receiving a full charge from your "underdriven" alternator. The cheap fix for this is to adjust your idle to 750, 900 or whatever until you get a full charge. The dealer or performance shop must adjust your idle, unless you have an ECC programmer (software and cable). There are companies that sell underdrive pulleys that DO give you a full charge when you are at idle on a stock Mustang (at the expense of a little more HP lost to drive the alternator). Inquire to the dealer that you are buying the pulleys from "At what RPM does the alternator pulley give my battery a full charge?" They will tell you. Underdriving the water pump does not cause problems.