Could you elaborate on this a little more 5-90? I know I'm not the original poster but I'm interested in the process. Also what's your opinion of doing this and how many horses this would free up?
Parakeet
"Belt wrap" refers to the angle that would be included in the arc where the belt touches the pully. One-quarter way around is 90*, one-third way around is 120*, one-half way around is 180*. The more torque you have to transmit via belt, the more wrap you need (the most you can practically get, using idler pullys on one or both sides, is about 270-280* of wrap.)
For the power to be freed up, it depends largely upon the power draw of each individual accessory. Removing the aircon is probably the biggest gain (replace with an "AC Delete Pully" or a "Dummy Pully" as I mentioned earlier,) and you'll pick up whatever the aircon was drawing (but only if you routinely have it turned on. When it's off and the electromechanical clutch is released, the pully is essentially an idler anyhow.)
I don't have any specifics on what the mechanical fan draws - but it's typically only a handful of horsepower (removing the studs and replacing with the short screws is done simply to get you some more working clearance.)
Power Steering is usually a fairly heavy draw (most hydraulic pumps are,) but you'll probably want to keep that.
The power draw of the alternator varies according to current output - the more current you need, the more resistance to turning and the more force it takes to turn.
Eliminating idler pullys will do effectively
nothing to give you back power. Yeah, you'll get some (purely nominal!) gains from reducing the driven mass of the belt and associated system, but that's about it - and it's not worth bothering with, unless you're trying to wring
every little bit of power out of your engine. Even then, you really only do this if you've already done everything you possibly can to the engine internals (head flow work, valve port flow work, rollerised rockers, rollerised lifters, ...)
The guidelines I've given for belt wrap might be a bit off - as an error on the side of caution. If you get some extra wrap, that doesn't mean you're going to put more power into an accessory than it needs - that just means that you're less likely to have belt slip under load. Non-cogged belt drives work on friction, and increasing wrap increases friction between the belt and the pully. (A cogged belt - like a timing belt - is a "positive drive" system, akin to a chain/sprocket setup. The accessory drive belt is a "friction drive" setup - and you need a certain amount of friction for effective power transmission.)
