Edelbrock Performer RPM cylinder heads were ported by Brian Haflinger at IMM Engines, and were then fitted with Manley SS severe duty valves and COMP Cams beehive valvesprings. A COMP solid, flat-tappet cam with 260 degrees of duration and .586-inch lift tips the Pro Magnum roller rockers. The simple but very functional combination of a Holley 750-cfm carb and Edelbrock Super Victor intake feed the hungry beast.
The original four-speed manual transmission was put on a shelf. Instead, a competition-ready 904 was built by Pro Trans, complete with a low gearset to improve launches. A relatively mild 10-inch torque converter with a stall speed of 3,500 rpm was selected, and a Precision Performance Products shifter keeps Doug in total control of the tranny.
The interior found another Sloan at work. Mom went to work installing new repop seat covers and detailing all of the original dash trim. When the buildup path for the car departed from driver to performance, the interior required some upgrades. A rollbar makes the car legal for dragstrip passes just shy of the 9.90 mark. It also creates a proper place to attach the Crow Enterprises safety harnesses. The factory gauges still reside in the dash, but are obscured by an Auto Meter Pro Comp playback tachometer. A pair of matching gauges mounted underdash keep tabs on the small-block's water temperature and oil pressure. Wear marks on the rollcage downbar testify to the use this car gets now. When Doug's not collecting trophies at car shows, the A-Body can be found at the dragstrip, clicking off 10.60s at 124 mph.
The rear suspension is a departure from a typical Mopar buildup. Instead of a thick pack for the rear leaf springs, Doug used split monoleaf springs. CalTracs traction bars eliminate spring wrap and plant the tires, while Rancho RS9000 adjustable shocks dampen up and down motion. Never heard of these shocks? You're probably not alone. These are popular for off-road vehicles, featuring nine settings of shock valving that you can select by twisting a knob. The e.t.'s that Doug turns on a small tire are testament that these shocks certainly aren't hurting the car's launch.
At the front, Doug combined tried-and-true Mopar components with some new technology. To gain disc brakes, '73 A-Body spindles were mounted to the car. This also provides a larger bolt pattern at the wheels. But rather than use factory rotors and calipers, a lightweight Wilwood kit was installed for high-performance use. He then added Firm Feel upper control arms. These A-arms are tubular in construction for higher strength and rigidity, and they accept the '73 spindles. Mopar drag torsion bars are used to spring the front while QA1 adjustable shocks dampen the movement. Between the QA1s up front and the RS9000s in back, Doug can fine tune the reaction of the suspension to accommodate track conditions, and also make a quick change from dragstrip tune to street tune.
The rear axle is the original Chrysler 83/4 housing, stuffed with a 4.30 gear and a Richmond spool. The original-design drum brakes were also left out back, and were balanced to work with disc brakes up front.
As is the case with nearly every project car, the cost ended up being significantly more than what was originally budgeted. Doug estimates that the total makeover of grandpa's Barracuda cost five to six times more than he originally had in mind. The three-year project brought Doug's parents and brother into the effort, giving them lots of quality family time that adult families rarely get. Doug says that the Barracuda wouldn't be what it is today without Bryan's knowledge of drivetrain combinations. With his help, the car just plain works on the dragstrip. We're sure it's far from Doug's young mind at this point, but we have to wonder who the car will be passed onto next.
A pair of '73 spindles were...
A pair of '73 spindles were swapped onto the car to gain disc brakes and the later, large bolt pattern. Wilwood disc brakes provide stopping power up front, while the factory drums do duty out back. The front suspension also uses Firm Feel upper control arms that offer positive caster for improved stability.
The rear suspension is a little...
The rear suspension is a little bit different than your standard Chrysler A-Body. Doug uses a combination of Calvert split mono-leaf springs, CalTracs traction bars, and Rancho RS9000 adjustable shocks. These shocks were designed for 4x4s, but offer adjustable valving to help Doug dial in his launch.