Ford Mustang - 3G Alternator Upgrade
Be it the popular Fox Mustang or a vintage example, increase your charging system’s output with a bolt-in upgrade
For many years, the Mustang was a simple car. The original dream of a small and relatively light platform with a small-block V-8 and rear-wheel drive, with a bunch of options to individualize the owner experience, has been a hallmark of the Mustang right up through the mid-1990s. Later into that decade, the Mustang started packing on standard features, safety equipment, and more, leading to the Mustang we see on dealer lots today. Sure it is still rear-wheel drive with a V-8 under the hood of the GT, but today you'll also be getting stability control, traction control, ABS, power everything, HID headlights, electric power steering (EPAS), and much more. All of these features add up to a lot of power consumption and it's not unheard of to find 130-160 amp—and in some cases 200 amp—alternators. However, the everlasting Fox era Mustangs, while short on electrical needs when new, often pull double duty as rolling concert halls, race cars, and more. Their stock 65-amp alternators just won't cut it when these cars start seeing electrical upgrades.
The alternator in the '86-'93 Mustang is considered a 2G alternator. It has a single power plug on the side of the case along with a bolt-on internal regulator and plug-in stator connection. The rectifier/power plug can be a fire hazard due to excessive resistance and poor internal design of the 2G unit. In 1994, Ford reengineered their alternator to fix these issues. The new 3G based alternator featured an internal fan design, integrated regulator, and higher output. But don't think that a 3G alternator upgrade is just for late-model owners. The 3G unit uses the same 7-inch spacing (from pivot to fixing holes) as the '65-'85 1G alternator. This means you can upgrade your vintage Mustang, Mustang II, or early Fox's 1G unit with the power and reliability of a 3G alternator.
The 3G alternator starts at an impressive 95 amps, but you can also find 130-amp and higher models through aftermarket sources. One such source is PA Performance. PA's alternators are 100 percent new and fully load tested during assembly. They also include the voltage regulator and correct pulley. The 130-amp model, which we're installing here, puts out 80 amps at idle and a maximum of 160 amps! That's nearly triple the output for a bolt-in charging upgrade. Your stereo amplifier, aftermarket ignition box, high-output coil, and more will thank you for this upgrade!
The 95-amp unit is indeed a direct fit into the Fox-body's cast aluminum mounting bracket, while the 130 amp unit requires a minor amount of bracket trimming to clear one of the alternator case bolts, plus an additional charging lead to support the increased output.
While PA Performance does sell direct, they have a large dealer network to order from, which can help with shipping times. In our case, Mustangs Unlimited was our closest dealer and since we needed a few additional parts for this aging '89 hatch, we got everything we needed from Mustangs Unlimited quickly.