If you're a classic Mustang veteran, you've seen your share of carburetor swaps. Over the years, many original Autolite 4100 and 4300 carburetors have been replaced by any number of aftermarket carbs, primarily the venerable Holley four-barrel. Holleys have provided dependable performance for over five decades, and they are still one of the most popular replacement four-barrels for vintage Mustangs. But what if you're a purist who wants to return to the Mustang's original fuel system?
Because the Autolite 4300, an emissions carburetor, quickly proved unpopular when it replaced the 4100 in 1967, many were replaced by Holley carburetors with their improved performance and solid dependability. The older Autolite 4100, based loosely on the Holley (power valve and accelerator pump design), sits on the same foundation as the Holley four-barrel. In fact, the 4100, depending on how you size it, offers the same performance features (and power) as a comparable Holley 4160. In other words, a 600-cfm Autolite 4100 will deliver roughly the same performance as a Holley of the same size.
We came up with the idea for this article when Thomas Voehringer wanted his wife's '64 1/2 convertible, which has been in her family since new, brought back to factory original condition. What bugged him was the old Holley replacement carb, installed years ago by his father-in-law, on top of his D-code 289-4V engine. That's when we called Jon Enyeart at Pony Carburetors. Jon knew exactly what type of Autolite 4100 to build, right down to configuration and the carburetor identification tag. Jon specified a C4GF-AE or C4AF-C Autolite 4100 with 1.08-inch bores and automatic choke for a '64 1/2 with four-speed manual transmission.