You’d be hard pressed to find an enthusiast who isn’t familiar with the Fox body Mustang, the pony car that brought Ford back into the performance fold by the time the mid-80s rolled around and fuel injection pushed smog-choked carbs to the curb. What’s less common knowledge, however, is that the Fox platform was deployed throughout the Blue Oval’s line-up in a variety of different guises, stretching all the way from its compact Mustang roots into the mid-size and even luxury segments.
These weird Fox body bedfellows serve a secret role amongst inductees into the cult of fast Fords who understand that, for the most part, Mustang gear will bolt up underneath Fox-derived sedans, wagons, coupes, and ‘utes. This has led to a cult of Fox fans who would rather their ride stand apart from the million and one Mustangs on the road, while taking advantage of the stallion’s deep aftermarket.
Uncommon Performance: 1978-1992 Fox Body Fords
In the mid-70s Ford was looking for a versatile vehicle architecture that could be used to underpin compacts and then stretched to also pull duty in the larger family car segment. Enter the Fox platform in 1978, which would become more and more important to Ford over the next decade and a half as full-size land yachts fell out of favor.
The Fox platform was rear-wheel drive and featured a unibody structure, matched with a live rear axle and a front MacPherson strut design, and it was available in four distinct wheelbases. While a Fox-based Mustang would debut as a 1979 model to replace the much-derided PintoStang Mustang II (along with a short-lived Mercury Capri sibling), the first Fox beneficiaries were the 1978 Ford Fairmont and Mercury Zephyr, replacements for the Falcon/Comet twins that would be offered as coupes, sedans, and wagons. Next up was the Mercury Cougar and Ford Thunderbird, the mid-size Ford Granada and Mercury Marquis, the Lincoln Continental, the Ford LTD, and the Lincoln Mark VII, each of which would sit on various iterations of the Fox chassis and undergo their own set of confusing evolutions during the course of 80s – and who could forget uncommon variants like the Ford Durango ‘ute?
Of this motley crew of characters, there are a few stand-outs that have transcended their more pedestrian roots to become popular favorites for hot rodders. Specifically, the LTD, Fairmont, and Thunderbird have long been drag strip denizens, and to a lesser extent, so have their more rare Mercury counterparts. The Lincoln Mark VII is also notable as an affordable personal luxury coupe from the 80s that has stood up remarkably well in terms of driving experience and performance potential.
Why these cars in particular? And how can you make them purr (or whirr, or whine) with the same authoritative growl as a Mustang? Let’s take a closer look.
From The Factory
When it comes to bolt-in performance, there’s little that will get you going quicker for cheaper in a Fox body car than Ford’s 5.0-liter H.O. V8. In fact, with very few exceptions almost every Fox platform name plate had access to the 5.0 in one form or another, but if you’re looking for decent stock power – or more – you’re going to want to source an H.O. or ‘High Output’ version of the engine. Snag a mass-airflow equipped example from a wrecked Mustang GT/LX or a second-generation Ford Explorer and you’re looking at roughly 225 horsepower and 300 lb-ft of torque.
Alternatively, you can try to build the 5.0 that’s already in your Fox, but be prepared to do some work to improve breathing if you want to approach the Mustang baseline. Most of the Fox 5.0 applications outside the ‘Stang were designed with a torque-happy power band, with the exception of the Lincoln Mark VII (which from ’87 onwards essentially matched the Mustang GT’s output with an optional and eventually standard H.O. V8) and the rare Ford LTD LX sedan (which featured up to 175 horses from its CFI 5.0 H.O. engine).
If you want to be different, you can try your hand at building the turbo four-cylinder or supercharged V6 engines that were offered with both the Cougar and the Thunderbird at various points during their evolution (with the V6 available in the MN12-generation ‘Birds and Cougars that followed the Fox platform). Versions of these motors beat out their stock 5.0 counterparts in terms of power, and there’s definite – although not nearly as cheap – potential locked up inside. It’s also worth knowing that should drag racing be in the cards, Ford’s ultra-strong 8.8 rear differential is an easy bolt-in for any small pumpkins you might encounter. A C6 or AOD automatic transmission will be your weapon of choice in any straight line war, but if you’re more inclined to go the three-pedal route you should remember that Ford’s T-5 manual is notorious for its inability to deal with substantial torque.
From The Aftermarket
This section could honestly be thousands upon thousands of words long, because the Mustang is one of the most over-served performance cars by the catalog crowd. We’ll spare you the endless list of 5.0 hop-up parts, because there are already innumerable guides out there for building whatever level of horsepower you want from this iconic engine.
Instead, how about some help with some of the Fox platform’s common weak spots? We spoke to Brian Gust from Maximum Motorsports, which in addition to being one of the top Mustang parts suppliers in the U.S. has also developed a reputation as a storehouse of esoteric knowledge about the Fox platform in particular.
“Always start with the chassis first,” Gust said. “A stiffer chassis is the key to both a good road car and a good race car. To get there, you’ll want to invest first in subframe connectors, and then rear lower control arms.” Brian also added that while Mustang front and rear control arms and caster camber plates are direct bolt-ins to the Fairmont, for example, other Fox platforms have subtle yet unique differences. On cars like the Fairmont that feature a longer wheelbase some subframe connectors and upgraded k-members can require modifications to properly install.
Gust also stressed that dampers make a huge difference on these vehicles. “Investing in a good set of shocks for your Fox can overcome even some of the factory-designed limitations inherent in the suspension systems of these cars,” he told us. “Dampers are the heart of your entire suspension build, and they can dramatically transform even an otherwise bone-stock car’s handling.” Polyurethane bushings – in the steering, control arms, and swaybars – are also a good bang-for-the-buck mod according to Brian.
Finally, you’ll also want to consider braking, especially if you are modifying one of the heavier Foxes such as the Granada or the later Continental/Cougar/T-Bird. Mustang Cobra brakes will fit up front as long as you put enough wheel on the car to clear the larger discs (at least 15-inches). Rear disc brake conversions from drum setups are also available.
From Left Field
Just like everything else on the planet you can stuff an LS V8 under the hood of your Fox body sleeper and stun everyone with your cross-brand sacrilege. There are also some fairly wild turbo setups that you can mate to a reasonably stock 5.0 V8 and make 11-second horsepower. But why not get weirder? There are a panoply of FoMoCo engines that fit under the hood of most Foxes, including the 235 horsepower 3.4-liter Yamaha-tuned V8 from a third-generation Ford Taurus SHO, a newer 5.0 Coyote motor, or even the (much more difficult to achieve) 2.0-liter turbocharged EcoBoost four-cylinder. If you want to go old school then Ford’s 460-cubic inch big block also clears what it needs to clear when settling between the front fenders of a Fox.
Or maybe you want to follow an even more different path than building a mere high performance alterna-Fox? If you’re a true glutton for punishment, and you’re idea of fun veers more towards miles per gallon than pure power, why not build the rare BMW turbodiesel engine that was available for a very brief period of time as an option with the Lincoln Mark VII? This 2.4-liter straight six originally put down 115 horses, and with only 400 examples known to have left factories, you’d likely be the only one on your block with a BMW-powered Ford.
Remember, a Fox body Ford – regardless of what shape it might take – can easily be made as fun and as fast as its Mustang cousin, while avoiding the pony car image. Driving something different is often a lot more fun than simply joining the herd, and if you’re looking to find out more about how to trick-out your Fox, you can head over to the Thunderbird Cougar Club of America forums (also serving Mark VII enthusiasts) or the equally active Fox T-Bird / Cougar Forums, both of which serve as starting points. If you’re seeking parts or build advice, it’s never a bad idea to call the folks at Maximum Motorsports, either, which has been serving the Mustang and Fox in general since 1992 and which has compiled an extensive database of what works and what doesn’t on the platform over the course the past 25 years.