In the 40+ year history of the Mustang, there have been plenty of special edition models. From the High Country Special (1966-68) to the many incarnations of the Mach I, factory-modified Mustangs have always generated excitement, not to mention additional sales for the company. Over the years, the content of the various specials has ranged from cosmetic-only, stripe and scoop packages (think 1976 Mustang II MPG Edition), to those minimally-produced, homologation specials such as the ground-pounding BOSS 429. As it happens, all other special editions don't necessarily sit somewhere along a straight line that connects these two examples.
A couple of cars, at least, followed a road less travelled. One of those is the SVO Mustang, which was produced for the 1984 through 1986 model years and managed to record sales of less than 10,000 units over the three years. Those production numbers, by themselves, are enough to lay a certain exclusivity on the SVO model, but there was a whole lot more about the car that was unique.
That is exactly what 14-year old Craig Gillis discovered when he got the idea of buying an SVO that he'd seen for sale. Both Craig and his father routinely travelled the road to New England Dragway, in Epping, NH, on weekends to see the racing. Mustangs have a habit of running in the family, so it wasn't too surprising that young Mr. Gillis might start researching just what this SVO Mustang business was all about. That research eventually led to his purchase of the car for the princely sum of $1,400 and the investment of a couple of years in restoring the car before he could even drive it.
The newest SVO Mustang is now more than 20 years old. When new, it is said that a dealership salesperson never sold an SVO model - instead, the customer had already bought it before arriving on the lot. That customer, though, was a different one from the typical Mustang buyer. Recall that 1982-1983 saw the real rebirth of Mustang performance, following the mid-70's oil crisis difficulties.
From 1983, the 5.0-liter engine sported a 4-barrel carb, when mated with a manual transmission, to which it passed on 175 horsepower. This was a significant improvement from the previous year's 2-barrel version, at 157, or the dreaded 4.2-liter's paltry 118 hp rating. The return to the 5.0-liter engine was believed to be a stopgap measure by Ford, and that a turbocharged 4-cylnder mill would dominate the future. Late in 1983, that engine became available, pushing out 145 hp.
Regardless, Mustang GTs , GLs and GLXs with the 5.0-liter engine were flying off the dealership lots, with their power numbers almost 50 percent greater than two years before. In 1984, Ford released what they intended to be a BMW-fighter. With far more focus on handling and poise, the SVO Mustang featured a 175 HP fuel injected, intercooled and turbocharged 4-cylinder engine, Koni gas-pressurized shock absorbers, 4-wheel disc brakes, a Hurst shifter, Recaro seats and 16-inch wheels, just like the Corvette of that year.
All of the SVO's beauty wasn't just under the skin. These specialty cars were immediately recognizable as different from a production Mustang, even if you didn't know exactly what you were looking at. Starting from the single rectangular sealed beam headlamps, the front end of the SVO differed markedly from its siblings. A functional hood scoop, offset from the centerline of the car, was used to force air through the intercooler, while a wrap around front fascia panel adds a distinctive look without sacrificing cooling air flow. Fender flares, often referred to as 'spats' suggested a more aggressive stance, while different sail panels behind the quarter windows sloped back to a signature SVO dual wing rear spoiler. The SVO's unique tail lights would reappear almost a decade later to distinguish the first SVT Cobra, in 1993.
Fully armed with the knowledge of these differences, Craig - by now a 22-year-old defense systems engineer - and his father began by stripping the body down to a shell. The interior was removed and the car repainted by Scott Lockhart, of Bridgewater, MA, in PPG's 'arrest-me-now' Viper Red paint. Before reinstalling the interior, all cloth items were carefully reupholstered to bring back the SVO's original glory and feel.
We're guessing that Craig's dreams the night before his 16th birthday were not about what kind of cake he was going to get. Doubtless, he was already planning the what, where, who and when events of his first day with a driver's license. There's little to risk in guessing that his ride was one of the more unique cars to show up in the high school parking lot.
With 5 psi of boost, the intercooled motor was putting out 175 horsepower and, given the handling prowess of the SVO, it would certainly hold a surprise for anyone that thought they could dust off this Pony just by turning. Still, given that the car was 16 years old by then, automotive technology had advanced by furlongs ... at least. The throttle body fuel injection was leading edge stuff at the time it was originally built, but now it was holding back a motor that SVO enthusiasts well knew could take up to 30 psi of boost.
After three years of driving the car, Craig decided to enlist help from his cousin, Paul Slaney, of Plymouth, MA, to rebuild the SVO's motor. That process began by pulling the motor and stripping everything down to the bare, cast iron block. The cylinders were bored 0.30-inch oversize to accept new dish topped, forged pistons from Wiseco. After porting the cylinder heads, Paul installed the Ford Racing A237 hydraulic roller follower camshaft. The cam's 274 intake and 282 exhaust duration, coupled with a .420-inch lift has good idle characteristics and offers excellent mid-range horsepower on turbo engines.
To help feed that cam, Slaney hogged out the intake manifold as well and installed the 65mm throttle body from a 1995 Mustang GT, along with the needed adapter. On the go-juice side, fuel delivery would need to be ramped up to match the improved air intake. To manage this, a Walbro 255 lph fuel pump was coupled with a Kirban adjustable pressure regulator. At the other end of the pipeline was a set of new 52-lb.hr fuel injectors. Driving the whole forced air idea was a new Turbonetics T3/T4 turocharger unit, regulated by a Tiny Avenger bypass valve. With a target boost setting of 20 psi, upping the ante in the intercooler department was a must. Craig sourced the intercooler from an Isuzu NPR medium duty truck. He also fabbed up his own 2.5-inch intercooler tubing and you'll see from our photos that Craig did a top drawer job of that. On the lively side of things, ignition is handled by a MSD 6AL controller, a standard Ford ignition coil, Taylor wires and Autolite plugs. An SDS stand-alone engine management system was also installed to replace the throttle body fuel injection control system. To keep a close tab on the most vital functions, Craig added Auto Meter boost and fuel pressure gauges, as well as a SDS air/fuel ratio meter.
The remainder of the driveline has stayed reasonably true, although a Pro 5.0 shifter now sits atop the T-5 transmission, replacing the original Hurst unit. To keep the axles up off the ground, this Mustang relies on a set of 17 x 8-inch Eagle Alloy rims, wrapped in Goodyear Eagle 235/45-17 tires. Since completing these upgrades, Craig has taken the car to a couple of shows and was rewarded for his efforts. A second place from the World of Wheels show in Boston, along with a First in Class and Editor's Choice award from an FFW event in Epping are his to brag about.
Currently, Craig estimates that his 144 cid "Iron Duke" inline-four is pumping out around 280 to 300 RWHP - not an uncommon result for that boost level. He's still working to find a tune that will deliver everything he expects from the hardware, and when we last spoke with him, he was going to be visiting a new shop with SVO-specific tuning experience. Yes ... that's one of the consequences of loving unique cars. The average service facility is likely to treat it in an average fashion, and deliver average results. Just ask any SVO Mustang owner and I'm sure they'll tell you that nothing about their experiences or their car is average.
In fact, when they first reviewed the SVO Mustang in 1983 a major buff book said, "this may be the best all-around car for the enthusiast ever produced by the US industry." That's not a bad starting place whether you're 14 or 40.
Craig Gillis'1984 Mustang SVO
PPG Viper red paint, by Scott Lockhart, Bridgewater, MA
Auto Meter boost pressure, fuel pressure gauges; SDS air fuel mixture meter
Wheels And Tires
Eagle Alloy 17" x 8" all around, with Goodyear Eagle 235/45R17 tires
I would like to thank my father and my cousin, Paul Slaney for helping build this car. I would like to thank my dad for the use of his garage for building and storing the car. I would also like to thank my Mom for being understanding during the process.
Craig Gillis' 1984 Mustang SVO
Ford Turbocharged 2.3-liter I4
Block bored .030" over for Wiseco forged aluminum pistons; Ford Motorsport A23Y roller camshaft; Cylinder head ported by Paul Slaney, Plymouth, MA; 1995 Mustang GT 65mm throttle body with adapter; Turbonetics T3/T4 turbocharger; Kirban adjustable fuel pressure regulator; Walbro 255 lph fuel pump; Adapted Isuzu intercooler with own 2.5" piping; Tiny Avenger Bypass valve; MSD 6AL ignition controller; Taylor plug wires; SDS stand-alone engine management system
Pro 5.0 short throw shifter
280 - 300 RWHP (est.)