Supercharger Drive System for the Ford 03-04 Cobra 4.6L DOHC

Supercharger & Drive Components

Generator/Alternator & Pulley

The Generator/Alternator Pulley is located to the drivers side lower front corner. The pulley itself is 8mm wide and is sold separately from the Alternator. This Alternator is specific to the 03-04 Cobra, where most Alternators mount up high in the middle of the Engine, the Supercharger occupies that area on the 03-04 Cobra, so it was moved. The Alternator requires a Upper and Lower Mounting Bracket, these are very rare and if priced right, should be purchased if found in good condition. There is also a small adapter that is used to turn the electrical connection 90̊, so it doesn’t interfere with anything, make sure you get one. I have heard of several owner having trouble with there Alternator, the main culprit is higher then expected RPM’s and heat. Many have suggested that using a Performance Pulley Kit, which slows down the Alternator, helps with this situation. I personally don’t think it is any one problem, more like a combination of heat, high electrical load, high under hood temps, and perhaps high RPM’s

Alternator:

Alternator Pulley (8 Rib)

Alternator Pulley (8 Rib)

Crankshaft Pulley Extension
Bracket

This is mounted to the front of the Crankshaft Pulley, and uses an additional Brace/Bracket to help control the heavy load placed on it by the Driven Pulleys it turns. The Support Bracket must be removed with the Pulley, by simply loosening three fasteners that hold it in place. Another useful tip, is that the Pulley is LEFT handed. To remove the Pulley you have to turn it clockwise. These Pulleys are tightened to 100Nm or 74lb-ft, so they require some effort to remove, and something to hold the Flywheel. Ford makes a nice little part, #303-673, that fits in place of the starter and holds the flywheel from turning.
This assembly is another hard to find item and should be purchased if you happen to run across one at a reasonable price.

Crankshaft Pulley Extension: 2R3V-6C254

Lower Support Bracket 2R3V-10153

Lower Bolts(2 Req’d) 2R3V-N605909

Fly-Wheel Holder: 303-673

Above: This is a brand new Belt Idler Support Bracket, as furnished from Ford. As you can see it comes with the Tensioner and Idler Pulleys attached. You will need the 5-bolts to install it.

Belt Idler Support Bracket

This piece is also refereed to by many as the Cross Brace or Cross Support or Bridge Support. This is a good sized Cast Aluminum piece that crosses the front of the Engine and straddles the Accessory Drive System so the Supercharger Drive System can operate in front of the other System. This brace allows the two Drive Systems to work in the same area, on different plains, without interfering with each other. This is also a part that is specific to the 03-04 Cobra Engine, and should be purchased if you run across one at a fair price. But be very careful, I have seen used ones go for more then a new one can be purchased for on sites like E-bay. Clearly a problem with the bidder not knowing his subject, it’s history or current selling price. For dress-up, I am going to have one of these Cross Braces polished, it is a smooth cast part and should polish out well, of-coarse this is for looks only and would not be required for a normal car. The Cross Brace is held in place with five bolts. It supports one Belt Tensioner and two Idler Pulley’s, all of which come with the cross brace when purchased from the factory.

Belt Idler Support Bracket: 2R3Z-6B209-BC

Idler Pulley: 2R3Z-6B209

Belt Tensioner: 2R3Z-8678

Mounting Bolts:(3 Req’d) 2R3V-N808920

Above: The Top pictures are the Supercharger Idler pulley, it comes like you see it form the factory. The Middle Right is the Alternator Lower Bracket, and the Bottom pictures are the Alternator Upper Bracket. The left Bottom is an idler Re-positioner kit, this allows you to move the Idler Bracket up and in on the Supercharger, for better Pulley Traction. You can also get replacement Pulleys to match the aluminum Pulleys shown.

Supercharger Idler Pulley

Alternator Bracket Assembly &

Lower Alternator Support Bracket Lower Alternator Support Bracket

This Small Pulley and Bracket are located right under and to the Driver Side of the Supercharger. This Small Bracket attaches to the Head and is used to support and mount the Idler Pulley and Alternator Upper Bracket. This is also the same Pulley many move up and in, to wrap the Drive Belt further around the Supercharger Pulley, for better traction. They sell a kit that moves this Idler Pulley up, and I have found it to be a worth while investment. The further you can wrap the Drive Belt around the Supercharger Pulley the better it will work, creating more surface tension and reducing belt slip. The Bracket is also used to help support the alternator, hence the name, Alternator Bracket Assembly. As you might also expect, this Bracket is specific to the 03-04 Cobra and again very hard to find on the open market. I would buy one if I came across one, so long as it was priced accordingly, just remember they are still available from Ford. There are too more Alternator Brackets, the upper and lower ones. These are almost never on E-bay, and should be purchased from the Local Ford dealer.

Alternator Bracket Assembly: 2R3V-17K814- AA

Mounting Bolt:(2 Req’d) 2R3V-N811268

Lower Alternator Bracket: 2R3V-10153-CA

Mounting Bolts:(2 Req’d) 2R3V-N605909

Above: Left is a kit to make changing Supercharger Pulleys very easy. The Stock Pulley is removed and in it's place a new Collar that locks onto the shaft, then the new Supercharger Pulleys can simply bolt to the Collar. This makes changing the Pulley Sixe a snap. The above pulleys are 2.90" & 3.10", both are Diameter measurements. On the Right, is an example of a popular Supercharger pulley removeal & Instalation Tool. The Pulleys are pressed on to the Supercharger Shaft, and HAVE to be Pulled off or Pressed on. DO NOT HAMMER on the shaft, you will damage the Supercharger Shaft, Bearings , Coupler and Rotors.

Supercharger Pulley

The Supercharger Pulley is located on the snout of the Supercharger, pressed on to it’s shaft. Many owners change the mounting and size of the Supercharger Pulley. There are several manufacturers that make a bolt-on Pulley Kit. This allows the owner to quickly and easily change the Supercharger Pulley by loosening a few screws and removing the Pulley. No more press on fit, and using a Special Tool to remove the Pulley form the shaft. This new method uses a small metal collar that is pressed onto the shaft, then the Pulley is bolted to it. Now feature changes can be made very simply, by just removing 4 small screws. The reason many owners like to change the front Pulley is to increase the Rotor Speed of the Supercharger. Since this is a Positive Displacement unit, it delivers the same amount of air to the Intake System with each 360̊ rotation of it’s shaft. If you can speed up the Rotors, with out speeding up the Engine, you can get more capacity from the Blower without turning the Engine any more RPM. This extra capacity means more Boost Pressure, and more power. The stock Eaton Blower is factory set at 8 psi of boost, but many turn the Rotors faster to get 14-16 psi of Boost. This usually requires a Port Job on the Blower and a change to the Engines Tune, so be careful to not over step your Engines bounds.

Drive Belt

The stock Drive Belt is part number 8620, the same as the Accessory Drive Belt. But before you purchase one make sure you know which Blower Pulley you intend to run. By changing the Blower Pulley and or the location of the Supercharger Idler Pulley, you may have to purchase a new longer Belt. Belts are very common and can be purchased at any auto parts store of your nearest Ford parts counter. Just be certain to use the right size and a quality Goodyear or Motorcraft belt.

Supercharger Drive Belt: 8620