Jim Smart
June 12, 2014
Photos By: The Manufacturers

Autolite or Motorcraft?

Ford’s Motorcraft name originated in the ’50s; however, it was not very successful. In 1961, Ford acquired the Autolite name, along with its assets, including a spark plug manufacturing facility and a battery factory. Ford very quickly began using Autolite products as original equipment in new vehicles. In the years to follow, Ford would be involved in a lengthy federal anti-trust lawsuit that ended in 1971 when it was forced to sell its Autolite Division to Bendix.

When Ford sold Autolite, it came up with a marketing solution known as Motorcraft. It brought back the old name and managed to make a success of it. This is why the Motorcraft name appeared for the second time beginning in 1972. This is also when the 1G alternator became a square case with the Motorcraft name. The Motorcraft name did wind up on some round-case alternators toward the end of round-case production in 1971-1972.

Motorcraft Alternator Quick Reference

1G: 1964-1986

The original Ford alternator rated at 38 to 55 amps. It is externally regulated. It can be upgraded to 65, 95, 130, or 200 amps, though you are better off going to the 3G if you want over 95 amps.

2G: 1982-1993

The 2G is the second generation Ford alternator, internally-regulated with multiplex plug in 65- and 75-amp ratings. It can be upgraded to 130 and 200 amps, though not recommended. The down side is the underrated plug and wiring, and corrosions issues that cause high resistance, heat, and fire.

3G: 1994-present

The best bang for the buck there is for classic, Fox, and ’94-’98 Mustangs alike. The 3G is an outstanding alternator for the money and is easy to install in any application. Never use the 2G plug in a 3G swap. It will overheat and catch fire. The 3G is available in 130 and 200 amp ratings.

4G: 1996-2002

The 4G is a pancake version that looks like the 3G, which makes it ideal for tight installations. The 4G is available in 150 and 200 amps, and was OE on the ’96-’02 four-valve Modular and Bullitt models.

6G: 1999-present

The 6G arrived on the ’99 Mustang and could also be found on the ’02-’04 four-valve Modular. It was also used on the all-new S197 Mustang for 2005. It is designed primarily for late-model Mustangs. It is available in 130-, 170-. and 200-amp ratings.

Alternator Output Ratings

Information courtesy PA Performance

Engine RPM 1G 60-AMP 2G 75-AMP 3G 95-AMP 3G 130-AMP 3G 200-AMP
900 15 24 64 81 102
1,000 30 41 70 107 120
1,250 43 55 76 120 157
1,500 50 61 93 138 179
1,750 55 69 99 147 184
2,000 58 72 109 156 187
2,250 61 75 112 160 194
2,500 63 78 114 167 199
2,750 65 80 116 174 204
3,000 66 81 122 181 207