The alternator. Hardly a performance part, or is it? Modern vehicles are loaded with more electrical componentry than ever. Not only are the power-trains entirely electronically controlled but there are more creature comforts than ever, such as DVD and navigation systems to name a few. Of course the aftermarket has followed to suit. Just look at the host of electronic performance products on the market for the 4.6L and 5.4L modular motors. You have electric waterpumps fully rated for street use. Add in high-volume EFI fuel pumps, or perhaps a methanol injection system to chemically cool your boost charge. We haven't even touched on the subject of audio performance.

The automakers have long realized the antiquated 12 volt battery and 14 volt charging systems are inadequate. In fact it will only be a matter of years before all new vehicles use 42 volt charging systems and 36 volt batteries. Incidentally, voltage starts becoming deadly around 50 volts and higher. Hence the internationally agreed upon 42 volt limitation for automotive systems.

In the mean time what is a late-model Mustang enthusiast to do if he wants to add in high power demanding accessories, such as amps and subwoofers, or perhaps a gauntlet of electron demanding performance parts? In our case we are installing a Nitrous Works nitrous oxide system on our 2001 Mustang. Nitrous systems are an electrical nightmare. You

PA-Performance 6G with chrome plated body.
have nitrous, fuel and purge solenoids. A bottle heater, remote bottle opener, and a variety of switches and relays. You are easily adding a 20-30 amperage load to the system. The answer is get the biggest and baddest alternator you can find. Until now there wasn't much for a 4.6L Mustang (or other modular powered Ford.) The factory alternators put out just enough to run the car and all the stock accessories, about 105-120 amps. That does not leave much amperage to spare. Without an alternator capable of meeting the current demands of all these parts, the parts will not perform as expected. The last thing we want is a fuel solenoid or pump which does not open 100% due to insufficient voltage. Fortunately PA-Performance has addressed this issue by introducing a 170 and 200 amp power generating beast. Even more impressive is the unit retains the stock 6G (Ford's sixth generation alternator) external dimensions.

The graph above shows how our factory 6G alternator and PA's 200-amp unit performed on an alternator dyno.

An alternator dyno is able to load the alternator by applying a steady current demand. Eventually the alternator peaks out at a specific speed (alternator rpm is a function of pulley size and engine rpm.) Note how the PA Performance 200 amp unit hits 200 amps at 4000 alternator rpm, while the stock unit barely breaks the 125 amp mark past 5500 alternator rpm. Note that that alternator rpm is roughly 2.5 times engine rpm due to pulley ratio. In other words, the PA alternator is making 200 amps at below 2000 engine rpm!

We installed the 200-amp alternator in a matter of minutes (see below) and gave ourselves an electrical buffer zone for when we want to fire off a 150 shot of the laughing gas, or if we just want to cruise on a hot summers day with the AC blaring and sounds boomin'.

Installation: PA-Performance 200-amp 6G Alternator

Installation begins with disconnecting the negative battery cable.

Remove the serpentine belt by cranking back on the tensioner with a long 3/8" ratchet.

Remove the 10-mm. nut on the terminal and disconnect the power wire.

Using a 10mm socket, remove the 4 bolts and the alternator support bracket.

Disconnect the wiring harness plug to the alternator.

Backing off the two lower mounting bolts allows the alternator to be lifted out.

The case of the PA 200-amp alternator is just a smidge taller than the factory alternator.

The new alternator drops right into the factory location using the factory bracket and hardware, no modifications are necessary.

Due to the higher current we are stepping up to the PA 4-gauge power cable and fuse shown here. The stock 8-GA. wire is pushing it with over 140 amps.

The new power cable is connected to the battery terminal and routed alongside the stock wire.

The other end of the power cable is connected to the 12V post in the starter relay box.

There's the numbers we're after. At idle, with high beams on, AC blowing, radio on, and defroster on, the 6G cranks out 105 amps and keeps the battery at 14V. The stock unit hit 69 amps and battery voltage was in the low 13's.

In This Article:
An installation and review of PA Performance's new 200 amp 6G alternator for 4.6L 2V engines.
A high output alternator is good foresight for our planned high-amp draw accessories such as nitrous solenoids, bottle heater, and switches.

Watts Up?
In a 12V system a 1000-watt stereo draws 90 amps, using the formula:

     Volts x Amps = Watts

In reality the draw is over 100 amps because no electrical device is 100% efficient. If an alternator is rated at 105 amps and we figure the vehicle accessories and engine require 50 amps, that leaves a mere 55 amps for the stereo and other stuff. Clearly not sufficient to power the big amps in a 1000 watt system. This will result in poor performance and a dead battery

G Whiz
Ford (Motorcraft) Alternators Generations by Mustang Years
Gen. Model Years Amps.
1G 65-85 40-55
2G 86-93 65-75
3G 94-95
96-98 4.6L 2V
4G 96-02 4.6L 4V 130
6G 99-04 4.6L 2V
02-04 4.6L 4V
Source: PA-Performance







PA Performance
P.O. Box 31
Frederick, PA 1943
Ph. 877-471-8010
[email protected]



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