On Sunday, May 27, 1979, hundreds of thousands of racing fans watched as Sir Jackie Stewart, three-time F1 World Driving Champion, drove a specially built Ford Mustang around the oval track at Indianapolis Motor Speedway to begin that year's race. Three '79 pace cars had been built for the event, one of which remains in the Speedway's museum at Indy. Aside from gaining the prestige of pacing this famous race, the '79 Mustang was also the first pace car ever to be used for backing up the field during caution periods. Don Bailey took over the driving chores during the race, which was ultimately won by pole-sitter Rick Mears.
To commemorate the event, Ford offered a pace-car replica option on the '79 Mustang, which included the special paint scheme, interior treatment, and graphics of the original cars. The production cars could be delivered with the 2.3L turbocharged four-cylinder engine, or the 302-cid V-8 with two-barrel carburetor. Around 11,000 were built for the public. These cars were the first special-edition Fox Mustangs and remain collectible to this day. Some have had easier lives than others, and one of the less fortunate ones fell into the hands of Kevin Robinson in 1998.
"I've always loved the pace-car body style, and I found a rust-free car in New York," Kevin says. "I drove the car for a year before it was torn apart." This was far from his first encounter with ponycars. He had previously stabled a '66 Mustang 2+2, an '83 hatch he'd fitted with mini-tubs and a big-block motor, as well as a '93 Mustang that has also received the big-block treatment. (Apparently, he also had a dalliance with a '67 Impala SS, but we won't talk about that.) From his previous experiences, Kevin knew he would need a well thought-out plan for this latest project.
Keeping Pace
For help with that part of things, he got in touch with D&D Automotive Specialties in Whitehall, Pennsylvania, and things began to come together. "Bob and I were able to put a plan in place to build a reliable setup. This car was to be a mid-11-second combo."
The advantage of starting with an early Fox Mustang is that they're relatively light. However, the 302-cid V-8 engine in Kevin's car still suffered from smog control-induced anemia and would need a significant warming over to get into the 11s. The job was begun by removing the engine block and sending it out to Rebel Machine in Columbia, South Carolina, for cleaning, decking, and a 0.030-inch overbore on the cylinders. When it came back, Bob at D&D started the build by balancing a Scat stroker crankshaft that would, in combination with a set of forged SRP pistons, take the total displacement out to 331 cubic inches. The flat-top pistons were riding on a set of forged steel connecting rods, also from Scat.
The original cylinder heads were replaced with a set of Edelbrock Victor Jr. aluminum pieces that feature large-volume, high-flowing 210cc intake ports and 0.130-inch raised 75cc exhaust ports. The heads were built up using Ferrea stainless steel valves (2.05-inch intakes, 1.65-inch exhaust), Comp Cams' double coil valvesprings, and steel retainers. Once a custom-ground camshaft was dropped into the block, the heads were added, along with ARP studs, solid lifters, and 1.6-ratio roller-rocker arms. A Canton 7-quart steel oil pan went on the bottom to hold Kevin's supply of Amsoil 0W30 lubricant.
Nobody's Fuel
Next in was an Edelbrock Victor Jr. aluminum intake manifold, to take advantage of the CNC gasket-matched ports in the heads. Just before dropping on the Holley carburetor, the plate for a Compucar wet nitrous system was added, jetted for a 75-shot of booster juice. Once you go with a wet nitrous system, you'll need to ensure that the fuel system has the capacity to keep up with your demands of the engine. To do this, a Holley 140-gph fuel pump draws street gas from the 8-gallon RCI fuel cell out back, and a Mallory return-style fuel-pressure regulator handles the control functions. When Kevin decides to let the nitrous flow, an MSD window switch and a wide-open-throttle switch make sure conditions are just right. On the sparky side of things, an MSD Ignition 6T controller box and Blaster ignition coil begin the process to deliver a high-voltage signal to the Autolite 3724 spark plugs.
As built, this motor was going to put out some respectable numbers, so attention also needed to be paid to the car's driveline. The original factory output of 140 flywheel horsepower, and 240 lb-ft of torque just couldn't be depended on to hold everything together, so the C4 automatic transmission was the first part to be rebuilt. After fitting with a new Torque Converter Services' 8-inch, 3800-rpm stall converter, a new steel flexplate from JW Wheel and a Trans Specialties' transbrake, a TCI aluminum trans blanket finished the job nicely. Moser Engineering axleshafts and a spool looked after the rearend needs.
Setting up the rest of the chassis came down to Strange Engineering's front struts and rear shocks, Eibach front springs, and a set of UPR's chromoly steel control arms. These act together in a supporting role for the Centerline Convo Pro rolling stock in big-and-little configuration. Mickey Thompson 24x3.5-inch front tires are mounted on the 15x3.5-inch-wide alloy wheels, while the stern end shows a set of Mickey's best in the 28x10.5 size on 15x8.5 rims.
As shipped from the Dearborn Assembly Plant, the '79 Mustang had some cutting-edge lines that still look sharp today. For Kevin's car, these were augmented by installing a 4-inch cowl hood and laying on some PPG Zinc Yellow paint. Streamline Autobody, from Blythewood, South Carolina, did the exterior work. Inside, the major change is the addition of an eight-point rollcage, along with poly race seats and a five-point safety harness.
With everything back together, it was time to strap this Fox onto the dyno and see what the results were. At the end, Kevin walked away with a dyno sheet that documented 358 rwhp and 348 rwtq, all on 93-octane pump gas. Those results were pretty gratifying for Kevin, who wanted to pass on a message to our readers.
"The biggest thing I learned from this car is to get a plan and stick with it. Don't try to build beyond your budget." Kevin's original plan for the car was to run in the mid-11-second range. Now, he tells us, "After four years of running and tweaking, it has proven to be a solid 10.80 car on motor, with high 9s on a small shot of gas." Indeed, Kevin reports his best run as a 9.96 at 135 mph at Carolina Dragway.