I have been building an AC compressor bracket. In my build the Sanden 508 compressor will be mounted over the right valve cover, and will require a long 73" single V belt. The belt will go from the crank-power steering pump-AC compressor-back to crank. If needed I have built an idler pulley that would go between the PS pump and the AC compressor. I was reading a post somewhere, in which the guy said using a single belt (crank/alt/AC) was trouble some. Any thoughts about my system ?
No problem. My 508 is driven by a single belt that is turned by the crank, and services the water pump. The other groove runs a small belt to the alternator.
You have to limit the torque you load the belt with. The Sanden has a lower power draw than earlier OEM compressors. Running your fan, power steering a/c, and alternator with one belt will lead to shorter belt life and slippage under wet conditions. Keeping the belt tight enough to minimize slippage and noise will most likely over tax the bearings with excessive side load. It’s best to emulate OEM routing. A serpentine belt is required with tensioners and wrapping idler pulleys are a different animal than a v- belt.
I used from NAPA, the top of line Gates V- belt on two different cars, both with SBC never had a problem, AC around Water pump, crank, Alternator and Power steering had separate belts, 3 V pulley on crank on car with power steering.
Here's mine, The crank would slip and squeal, so I added a belt from water pump to the crank, semi loose fit, no adjustment. A/C works great.
Like others have said, the belt life will be a concern but maybe not so much on a car that's not a a dd. My experience says that the wrap of the belt on the crank pulley is critical on a single belt setup. If you look at a factory serpentine belt, they will usually have idlers to increase the wrap on the crank, usually making contact with at least 1/2 the pulley. Every inch of contact will help. Google "belt routing diagrams" for examples. Most of the pictures are for serpentine belts but the same principle applies to v-belts.
My AC compressor is driven by a dedicated belt as the PS. The alternator shares with the water pump. If you can, keeping everything tucked in and a 3 groove on the crank makes things pretty easy.
I think more than anything, having a good wrap on the driven pulleys is the key element. What these pictured setups all have in common is that there is almost 180 degrees of belt wrap on each pulley. Provided you have a similar situation, I see no reason why it wouldn't work.
The belt wil be going from crank-Power steering pump- AC compressor, the PS pump will be the adjustment point. The crank -Alternator - water pump will be run by a different belt.
Looks much like mine. I started with an Alan Grove bracket. That is not designed to clear anything but the stock exhaust manifold, so I bumped it out to clear my header. That modification slightly decreased the water pump pulley wrap, and slightly increased the compressor pulley wrap. It did not seem to make a difference.
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