genep

one last problem, I put a 454 in a 78 vette , used all the pullys from a 74 , problem is the water pump pully, if I use the 454 long water
pump pully ,there is enough clearance for the idler, I am not sure if it is the right setup. if I use the short water pump pully I cant use the idler because the pully size is larger on the short pump, so I cant get tension on the belt, do I have the wrong pully ? do I need the belt on the water pump to crank?
Thanks Gene

toobroketoretire

All of the 454's in C3's used short water pumps....................

71 Green 454

If you can't get tension on the belt with the short pump, is it because the belt it too long? If so, get a belt that fits snug on the water pump to crank pulley. That way the idler pulley will only have to go in slightly. I install mine on the crank first, then put in on the w/p pulley, then put the pulley on the water pump.

Yes, you should install the water pump to crank belt.

LS4 PILOT

It's a very precarious fit .....use the 74 AIM......even a washer or small,spacer can make a significant difference .

I use the expensive ...belts from Quantum belts .......they are available per the original GM part numbers .

As mentioned above , the belt must be a specific length , it's a snug fit , as the tensioner you noticed has limited travel.

That belt from Quantum is very correct .....and not cheap .....but it lasts a long time.

The above description sounds like the order I used too .....I do recommend using it as well.