BBK Underdrive Pulleys

[slappy9090]

I just ordered BBK aluminum underdrive pulleys, and the A/C delete bracket to move my P/S pump up, and also removed my smog. I was running into an issue finding a belt before the pulleys. I had 71 1/8" O.C and it was too short, 71 1/2" O.C was too big I am hoping the underdrive pulleys solve this. Has anyone had a similar issue or does anyone know if it will solve my belt lengeh issue I was having before???

 

[Mustang5L5]

You have a 3/8" difference in belt lenght there. The tensioner should easily be able to take up the differnce there so that you have about 1" of range or perhaps more.

Did you change how the belt runs with the smog deleted??

It should follow the path of the red belt here (but substitute the A/C for P/S in the pic). Get a peice of string and loop it around and measure. That should get you in the right range

 

[slappy9090]

The problem is the P/S pump actually sits somewhere between the old ac and original spot for the P/S. The angle across the tensioner to the P/S pump brings the belt too close together it will rub and not work. I have it routed just as the red belt shows and the tensioner just buries it on top of the water pump pulley. I am hoping the underdrive pulleys will fix it somehow by having different pulley sizes.

 

[RsStanG1987]

You need the smog delete pully other wise the tensioner is gonna bury right on that water pump pulley.

 

[Mustang5L5]

The problem is the P/S pump actually sits somewhere between the old ac and original spot for the P/S. The angle across the tensioner to the P/S pump brings the belt too close together it will rub and not work. I have it routed just as the red belt shows and the tensioner just buries it on top of the water pump pulley. I am hoping the underdrive pulleys will fix it somehow by having different pulley sizes.

DO you have the Ford Racing A/C delete kit that moves the P/S pump up?

That's the exact setup I have, with the smog pump deleted. I have my belt run like the red belt above and ther are no clearance issues at all.

Maybe you have something different i am not seeing. Got pics?

 

[slappy9090]

I do have the bracket. The 72.5 is really close, if I put it on there is maybe 1/2-1/4 inch between tensioner and W/P pulley. If I put any pressure on the tensioner it will rub I. This is why I am hoping the bigger pulley for the Alternator from the underdrive pulley kit will change the angle enough to fix it. I know alot of guys run this setup, thats why its so agrivating.