5.0 Mustang & Super Fords
1999 Ford Mustang Cobra - Party Crasher - NMRA Factory Stock Champ
Thanks To Shawn Johnson, NMRA Factory Stock Is No Longer Dominated By The 5.0 Mustang
Shawn soon learned that tuning would be a big part of his performance equation. "We found out that we were overloading the fuel system at 5,000 rpm," Shawn says. Ordinarily, this wouldn't pose much of a problem-but, remember, these cars use a returnless fuel system controlled by the EEC V. "You can't just throw in a bigger fuel system," Shawn says. "The computer drivers won't interact with the pump." This is where MD Performance of Cincinnati entered the picture. Using one of its fuel systems and Superhips Custom Tuning software, the fuel system woes and subsequent tuning issues were resolved simultaneously. "The new fuel system and tuning allowed us to make the engine very efficient-let's put it that way," Shawn allows.
Resting on your laurels is a luxury you can ill afford when competing in a stock class-especially when you're defending a title. "We're testing new parts from pistons to clutches all the time," Shawn says. "Diamond is helping us try different piston designs, and RPS Performance Products is working with us right now with its Cyn-R-G Segmented Flywheel and Max Series clutch. I really like it-it's an aluminum flywheel with steel pucks in it that don't warp like a steel ring insert." Another change for the better, Shawn says, is a new antiroll system by Gun Lake Performance that helps keep both wheels planted during a launch. Passing through the trunk, it doesn't interfere with the full exhaust system required in F/S.
As you might have guessed, constant change requires constant evaluation to determine if you are on the right path to improvement-however tiny that improvement may be. As such, Shawn has amassed a team that would make any Top Fuel driver envious. "Matt Wirt has been hired on as my chassis consultant, and he datalogs every launch, analyzes tire spin and suspension movement, then provides chassis setup recommendations. MD Motorsports does all our engine tuning and dyno testing. I've also got a crew chief, Ian Mullane, and he takes all of the info from the chassis guy and tuning guy and decides what changes should be made between rounds, plus fine details like launch rpm and shift rpm. All that varies depending on track conditions, weather conditions, and so on. They tell me what changes to make, and I do it. I like to remain hands-on."
Persistent protested teardowns (it's inevitable when you're the record holder) have also necessitated a dedicated engine builder. "It takes so long to tear down and reassemble one of these engines," Shawn says, "so now we're putting together a spare engine that we can put in the car while the other one is being torn down for protest."
So now here comes the million-dollar question: Is it all worth it? "If I break even, it's a good year," Shawn laughs. "But I don't have any other bad habits-I don't drink or smoke-racing is my only habit. And my wife, Christine, keeps me grounded so I don't get too carried away." Fortunately, racing is a habit the whole family can enjoy-in fact, Shawn recently purchased a motor home so both his wife and 9-year-old son, Tyler, can go to the races in comfort.
As of this writing, Shawn had just returned from Bradenton, Florida, where he won the class again-but just by the seat of his pants. "In the semifinal, I won with an 11.73 to an 11.61, and in the final, I won with 11.79 to an 11.77," he says. "Everyone was slow during eliminations-it was a lot hotter on Sunday and the track was getting greasy. But our mph was down to around 115, so now we're tearing everything apart to find out why the car is slowing down. The team I'm working with is never satisfied with 'good enough.' We'll analyze everything, put the car back together, and head to the next race."
And that, ladies and gentlemen, is what it takes to be a champion in the competitive world of Factory Stock racing.