DRIVE SYSTEM BASICS

The following information is provided to explain how the belt drive system ultimately affects available boost. The more belt traction obviously the more boost. Most late model supercharged applications use some type of serpentine belt drive of either 6 rib or 8 rib, therefore belt traction is generally not an issue. The standard ProCharger with a billet impeller and 8 rib drive is capable of well over 20 lbs. of boost.Carbureted applications may use a multitude of belt drive systems, the following are listed in order of increasing belt traction: • A single v-belt drive (how the A-6 a/c compressor was driven from the factory) • A twin v-belt drive • A 6 rib serpentine drive • An 8 rib serpentine drive • A tooth belt, or cog belt drive.

ProCharged applications that would use a singe v-belt drive, will typically yield 6-7 lbs. of boost on small blocks and 4-5 lbs. on big blocks. Procharged applications using a twin v-belt drive system will create as much as 12 lbs. of boost on small blocks and 10 psi on big blocks, The difference is purely belt slippage. As stated earlier serpentine systems are capable of driving substantially more boost and horsepower. The determining factors for which belt drive system is available to you are many. If you strictly use the original air conditioning brackets to install yourProCharger, you will use some type of v-belt drive in most instances. if you have a 1980'svintage carbureted application, or have access to factory serpentine pulleys, conversion to a serpentine drive system while still using the original brackets may be fairly simple and yield greater traction.If your requirements are only for 6-7 lbs of boost on a small block this can easily be accomplished. Whether you have a Chevy, Ford, Pontiac, Buick or Oldsmobile, simply bolt the ProCharger to the original air conditioning bracket and install a single v-belt to theProCharger as you would for an air conditioning compressor. Now if you would like a more substantial increase in boost and power, you'll need to go to a twin v-belt drive system. First you'll need to check to see if your basic pulley system is compatible with this. Many Oldsmobiles, Buicks, some Pontiacs and most Chevy's are. The way to determine this is fairly simple. 1) First determine the original pulley location of the A-6 air conditioning compressor.(This can be done using the ProCharger bolted to the vehicle as a guide). Typically most A-6 air conditioning compressors were driven from the rear crank shaft pulley groove. This is the groove closest to the harmonic balancer, or closest to the rear of the vehicle. 2) Determine whether there is room for a second belt to be placed in front of the original. The primary requirement is that the crankshaft pulleys be the same size for both belts, so that both belts run at the same speed. This is typically the format for most v-belt optioned Cheverolet big and small block engines and is commonly found in other General Motors engines. In fact if your engine has a two groove accessory (such as analternator or a power stearing pump) that was connected in line with the original A-6 air conditioning compressor, your engine is probably a candidate for a twin v-belt drive system. 3) Determine whether there would be any interference with the water pump or any other accessory pulleys if a second belt was used. Remember in most every case the secondbelt will be placed in front of the original belt. This means the second belt will be towards the front of the vehicle.Let's now look at belt tensioning systems. One of the main reasons why the ProCharger Universal system is so inexpensive is that in its basic form it is so simple. By simply bolting the ProCharger to the front A-6 air conditioning compressor brackets, this eliminates the need to relocate existing accessories (for space) and develop a different bracketing system for every different car and truck on the street. An added feature to this revolutionary system is that the original A-6 airconditioning compressor was adjustable in its location, and therefore the ProCharger when using these brackets is also adjustable in its location. This also means thatthe ProCharger will now actually slide to and away from the crankshaft pulley as the airconditioning compressor originally did. This means if the right belt(s) are selected there is no need for an additional idler pulley system. Simply install the belt(s) on the ProCharger, adjust it away from the engine, tighten the bolts and the belt(s) are tight. For many applications, this should be a suitable and inexpensive approach to installing the Proharger. However, if there are hood or valve cover clearance problems, the Pro ChargerTM will have to be installed with the use of an offset bracket or some other means of a custom drilled plate. In most instances theProChargerTM will be lined up axially (front and rear location) with the crankshaft pulley but insome vehicles with very low hoods or a tight engine compartment the ProCharger will have tobe moved an inch or two away from the engine (valve cover) and sometimes an inch or so down(away from the hood). ATI manufacturers offset brackets for Cheverolet big and small blocks. They are very similar to the original A-6 airconditioning compressor flat stamped steel bracket; however, they are manufactured from aluminum with mounting holes redrilled so that the supercharger is a few inches away from the valve cover and down an inch or so. These aluminum brackets, however, are not adjustable and are therefore drilled to accept an ATI idlerpulley and bracket. This idler pulley is adjustable and is used to tension the belt(s).The previous information was related to v-belt drive systems. Serpentine drive systems (6 or 8rib) are usually the best option, if available, for most street applications. Serpentine belts arecapable of substantially more traction and therefore are capable of more boost and horsepower. ATI offers turn-key kits for Cheverolet big and small block engines. These systems include complete bracketing, 8 rib crankshaft pulley, blower driven pulley, serpentine belt and an idler system, all in addition to the standard Universal kit (carburetor cover, air filter, discharge hose,oil system). If you don't need or want to purchase a complete system or don't have a Chevrolet engine there still may be quite a few serpentine options available. Many General Motors and Ford traditional V-8 blocks were upgraded in the early 1980's to serpentine drive systems. You may be able to convert your v-belt driven engine to a late model serpentine system. Even easier yet, you may be able to adapt one of these late model serpentine crankshaft pulleys onto the front of your existing v-belt crankshaft pulley, with a spacer plate to relocate the supercharger a few inches forward and connect the serpentine belt in front of your entire existing v-belt assembly. With just a little creativity a serpentine belt-driven Procharger can produce a reliable 800+horsepower on a daily driven vehicle. BACK