Does anyone know what the minumum contact area is on the crank pulley for a serpentine belt? I'm removing the power steering pump and relocating the alternator on my LT1. I'd like to avoid adding another idler pulley.

Also, does anyone know if serpentine belts come in many length increments? (like v belts do) I figured I'd design the setup, then cut the old belt to length. I'd take the old belt at the new length to napa and get the closest match. If they only come in specific sizes more than an inch or so apart in length I'd have to find the belt first and design for it.

When we setup the 914 V8 serpentine setup, I called "March" and If I recall correctly, they said you needed a min. of 40% coverage. I personally felt this could be less if you deleted the AC pump and powersteering pump. Yes. You can buy shorter belts. They are typically measured in metric increments. Not too long ago I was working on a shorter Boxster belt to delete the AC.


B

If you have at least one idler pulley, you should be able to find a belt to work with it. It helps to have a friend who keeps a whole inventory of different belts like I have. You just measure what you need and he finds it for me, if it is the wrong one, he will give me another one till we find one that works. Life is good sometimes.

I did a 914 V8 serpentine setup. I used a 6" Harmonic balancer from a 3.8 liter V6 engine and mounted a auto tensioner pulley on my custom water pump mount.
I started out on my conversion with a electric water pump and had mixed results with it.
With the electric pump I used a serpentine belt for just the alternator drive. It was easy to fine any length belt you needed. When I lazer cut my 1/2 inch steel alternator mount I even cut the belt length and part number into it.
I have no flex at all in my system unlike the ones from renegade that I have seen. I have over 8k miles on my car and had no trouble at all with the belt and turn my engine at over 7k rpms at times.

Bob

Cool, thanks guys. I'm running the AC compressor and idler/tensioner in the stock position (passenger side) and the alternator is being repositioned to the drivers side. Water pump is electric. I think I can manage 40%. originally it was something close to 80%. (all the accessories on one side) I'll be using the stock balancer (engine shelf is gone)

Ok, alternator mount is done. What do y'all think? Should I add another idler pulley between the alternator and the crank? The compressor will put an intermittent load on the belt, and it would have to go all the way around the alternator and back to the crank before it gets any real "bite". Perhaps this is a good thing as it would cushion the shock? Perhaps it's a bad thing?

(engine turns clockwise when viewed from this end but you probably knew that)

Now's the time to add an extra pulley if I need it... I need input from the experts! (the area is under 40% of the crank pulley...)