Rebuilding My Totally-Not-Collectible Mustang, Part 6

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You know, if Fox body Mustangs keep soaring in value I may have to rename this series of articles. And that would be a good thing.

My 1980 base model Mustang was originally equipped with a 2.3 liter, four cylinder engine, manual four-speed transmission, 13-inch wheels and a 7.5-inch rear end with a 2:73 open differential. Not exactly a performance monster, but in its defense, the car has traveled over a quarter of a million miles with nary a complaint and has been perhaps the most reliable vehicle I’ve ever owned.

American Muscle

Our rebuilding project began with the installation of a 347 Windsor small block stroker engine from McGunegill Engine Performance in Muncie, Indiana. The transmission was upgraded to a 5-speed Tremec manual.

The next major phase of the car’s rebuild is now complete with a little help from my friends at Late Model Restoration (LMR). I was having a hard time choosing between the TRX wheels commonly used on the early, performance-oriented Foxes and the later Pony wheels. But once we made the decision to upgrade to five-lug wheels, the rest was academic. TRX wheels are not available in the five-lug format, so I opted for LMR’s gorgeous chrome Ponies. Now that I see them on the car, I’m glad I chose them. They look incredible.

Additionally, the entire rear axle assembly was upgraded to a 9-inch Ford GT unit with 3:73 gears. The new 17-inch Pony wheels are huge compared to the stock 13’s, and somewhat larger than the 15-inch, four-lug Anson slots that had been on the car for the last decade. New Continental Extreme Contact performance tires were mounted. The entire stock brake system was upgraded with Late Model Restoration’s disc brake conversion kit. Essentially, my Mustang now has the brake system of a 2000 Mustang GT.

Although I’ve not yet conducted any acceleration tests, the performance and handling of the car has changed dramatically after the completion of this most recent phase. The 3:73 rear end is the most noticeable change. First gear launches like a rocket and demands an almost instant shift into second. Every gear now feels like a performance gear… even overdrive (fifth). I don’t need to downshift to pass anyone. I can stay in fifth and zoom from 55 mph to 80 in a flash. It’s scary fast. Perhaps the 3:73 is actually a bit too much gear. After driving about 200 miles I’m still undecided.

The new four-wheel disc brake system is outstanding, and a genuine necessity on a 400+ horsepower car. The brake pedal has superb feel and gives the driver great confidence. Track testing is yet to come, but these brakes are more than enough for street use. And remember, this 1980 Mustang weighs some 500 pounds less than the 2000 GT model for which this brake system was designed. That’s a huge advantage. I anticipate the brakes holding up pretty well under road course conditions.

An untimely December snow in central Indiana made photos a bit challenging, but I did the best I could under the circumstances. The next phase of our rebuild will include a complete suspension overhaul, including subframe connectors and lowering springs.

This is turning into a really fun car. Ford should have built it this way from the beginning.

Stephen Cox

Driver, FIA EGT Championship & Super Cup Stock Car Series

CEO, Sopwith Motorsports Television Productions

Co-host, Mecum Auctions on NBCSN

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Stephen Cox is a racing driver in the Electric GT Championship, the Super Cup Stock Car Series and the World Racing League endurance sports car series. He is also a television host and CEO of Sopwith Motorsports Television Productions. He is currently in his 10th season as a co-host on NBCSN’s Mecum Auto Auction. Stephen also serves as producer for the Super Cup Stock Car Series telecasts on MavTV and other programming on Fox, Outdoor Channel, Velocity and more. His past television work includes hosting: Champ Car World Series Indianapolis 500 NASCAR Winston West Barber Dodge Pro Series Paris-Dakar Rally USAR Hooters ProCup Stock Car Series Mid-American Stock Car Series ARCA Truck Series Stephen Cox is among America’s most versatile professional racing drivers. Few drivers have competed on both asphalt and dirt. Fewer still on both road courses and ovals. Fewer still in both open wheel and stock cars. And virtually none can add the elite division of off road desert racing to their resume. Stephen has not simply raced in each of these divisions – he has scored championships, wins, poles or top ten finishes in every single category, and in 2017 he adds the international Electric GT Championship sports car series to the list. From ARCA ovals to SCCA road courses, endurance racing to Rolex GT sports cars, from Tecate SCORE Baja Trophy Trucks in desert sands to the Hooters Pro Cup Series and Super Cup Stock Car Series on America’s famous southern ovals… Cox has driven them all, and won. Track record holder at Midvale Speedway (OH USA) Track record holder at Gingerman Raceway (MI USA) 18 career wins 17 career poles Mitsubishi factory test driver 2004 GT Challenge Series champion 2004 Championship Motorsports Association Rookie of the Year As a writer, Cox has authored: L&M PORSCHE; the story Penske’s 1972 Can-Am championship SHELBY LEGEND, TRANS-AM WINNER; the 1966 Ford Mustang Group 2 SCCA Racer AGAINST ALL ODDS; the 1970 24 Hours of Daytona Cox also authored the Small Team Sponsorship Guide for beginning sponsor-hunters, the classic book and seminar that redefined the way entry level teams attack corporate sponsorship.


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