The year was 1979. While Pope John Paul II's visit to the United States introduced car nuts like us to the bubble-domed contraption that became known as the "Popemobile," a bigger automotive breakthrough was introduced by Ford Motor Company; the Fox-chassis Mustang rolled off the assembly line at Dearborn. The new Mustang was Ford's attempt to revive Mustang, since Mustang II, the econo-version of the ponycar, failed miserably with enthusiasts during its mid-'70s run.
Today, despite the huge popularity of the latest-generation '05 Mustang, the '79-'93, better yet, '86-'93, fuel-injected 'Stangs, still have a strong presence on the street, track, and at the shows. So enthusiasts new to the game are buying the early cars (can you believe a Fox can now be considered an "early" Mustang?) because of their availability and still reasonable prices.
There's no way we can stop progress and we acknowledge that the '05 Mustang certainly deserves the high praise and aftermarket attention it's been getting from everywhere since it debuted. But we think it's important to take a retrospective look at the venerable Fox 'Stang, and point out some of the plusses that make it a great platform for new and veteran enthusiasts to personalize and modify at fairly modest expense.
It's not that we can't find anything notable about the true old-school Fox cars ('79-'86); but when you look at things from a "best" perspective, these Mustangs really came into their own in 1989. By this time, all of the bugs had been worked out and Mustang's two trim levels (LX and GT) had firmly established their identities. From a mechanical standpoint, '89 marked the introduction of the mass air fuel-injection system for the masses-all 5.0 Mustangs. Mass air was initially equipped on '88 California cars only.
With mass air metering, driveability improved, as did emissions and fuel economy. But that's not all. Mass air proved to be a lot more flexible to performance upgrades than its speed-density predecessor. Basically, the mass air EEC IV processor was better able to adapt to the modifications that were becoming popular-intake manifold and exhaust header replacements, bigger throttle bodies, camshaft and rocker-arm ratio upgrades, and, of course, nitrous oxide and small supercharger systems.
On the whole, the '89-'92 Mustang era could qualify as being the best for engine-mod potential because the 302 blocks were stronger, the aforementioned mass air system handled the metering requirements much better than the speed density system, the E7TE truck cylinder heads were very good and standard on 5.0s, and the engines featured durable, forged pistons (power-adder friendly) as opposed to the cast, hypereutectic slugs of earlier and later H.O. 302s. Plus, the '89-'92 'Stangs had horsepower rated at 225, which was 25 more than the Fox cars ever had in prior years. Finding a stocker from this period (yes, a few are still out there) would be an excellent starting point for a Mustang newbie. (Note: The California-only mass air system is year specific to '88. Mass air sensors from later-year Mustangs cannot be connected to the '88 system without first modifying the mass air wiring harness and connector on the vehicle.)