Mopar Muscle Magazine - 787-hp-challenger

1970 dodge challengerFeatured in Mopar Muscle magazine April 2000

"The problem with Mopars is... can't just buy the stuff off the shelf-it has to be custom built." said Doug Mace about his awesome '70 Challenger he co-owns with his brother Greg. That could explain the ten year build time it took the boys. While Mopars have always dominated the drag strips, ensuring go-straight goodies would always be available, their reputation isn't built on handling and road-race ability, so anyone building a corner burner is pretty much sailing in unfamiliar territory.


The Mace brothers shared a dream for about 15 years of entering a Mopar in the Silver State Challenge, a road race in Nevada held in cooperation with the Nevada Highway Patrol. Basically, it's an all-out race, with different average-speed classes to compete in, in addition to the "Unlimited" class, where you run whatcha brung for just over 100 miles. The Mace's were gunning for the Unlimited title. About the time they started this little endeavor, one R.J. Gottlieb was running a '69 Camaro known as "The Big Red One" and averaging 200 miles per hour. Getting parts, even ultra-high performance parts for a '69 Camaro isn't too difficult. Expensive, but not too difficult. Not so with a Mopar.

Motor and InteriorThe Mace Brothers' starting point was a cherry 38,000 mile, Slant Six-powered '70 Challenger. They bought it from a little old lady in California. "It was a really loaded California car; A/C, AM/FM, the body was really pristine, and a great thing to start with," said Doug.

They stripped the car and turned it over to Nathan Domries at Nate's Race Cars in Corona, California, who reinforced the body and suspension, and built the roll cage. "We wanted the car to be tough. Everything has been welded - the subframes, the chassis. Lots of time was spent building the car strong," said Doug - prudent actions when 200 mph is your goal. The front suspension is made up of reinforced factory components, augmented with a pair of NASCAR-spec torsion bars found in an old racer's garage, factory power steering, a heavy duty front sway bar, and KYB gas shocks. Stopping power is via massive 12-inch, four-piston JFZ disc brakes. Rear upgrades are a beefed 83/4 rearend fitted with Chrisman 2.76 gears, a limited slip unit, and Summers Brothers axles. Heavy-duty leaf springs, sway bar, and KYB shocks control rearend housing's movements, while another set of JFZ discs were hung on the ends of the tubes.


Challenger Burning Rubber

Rolling stock is 17x10-inch Budnik wheels with P275/40Z Dunlops up front and 17x12 Buds shad with P35/35Z skins out the back. What bodywork was needed was handled by Funny Car painter Doug Stabuck, in addition to installing a T/A hood and spoilers from Year One, before coating it all in House of Colors hues. Inside the full cage is a pair of 240Z bucket seats covered in black and gray tweed, Simpson 4-point seat belts, and a new carpet. A budnik steering wheel aims the car, while a full set of AutoMeter gages keeps tabs on the engine. The Mace Brothers are no strangers to speed, or the machines that create it. Doug worked on Top Fuel Cars for about 10 years, while greg has always been in racing and holds records on Pro Stock bikes in Canada. With that background, they knew what to use and where to go to get the most power. They found a '68 Plymouth Fury III 4-door someone had fitted with a Hemi to pull a trailer, and used that engine as the starting point! The '69 vintage block had been fitted with a rare set of K heads, and both the block and the heads were in excellent shape.


 Challenger Burning Rubber"We wanted the most outrageous, normally-aspired Hemi ever built," said Greg. With that gaol in mind, the block has been bored to 4.310 inches and stroked to 4.5 inches, for a total of 520 cubes. The holes were then filled with Carillo rods and 12:1 JE pistons. The heads were ported and fitted with stainless 2.25/1.94-inch valves actuated by stainless Norris rocker arms with a 1.7 ratio on the intakes and 1.5 on the exhausts. A Crane 270/276-degree duration roller cam with a .650-inch lift was dialed in with a Jesel belt drive, and stout 7/16-inch Smith Brothers pushrods motivate the valve gear. An MSD billet distributor with a 6AL box lights off the air/fuel mixture, and a full custom 3-inch exhaust system with Flowmaster mufflers aids in passing the spent gasses.


For induction, they started with a mgnesium Cross Ram, which made about 650hp on the dyno. Then they went to a dry sump oiling system in search of more, but had problems with room for the oil tank, so it got scrapped and was replaced with a custom Stef's pan. Next, a custom-made Craig Davis 2x4 intake that was a cross between an inline and a cross ram replaced the magnesium intake, and the numbers were up to about 700 horses. Then they went to the Lee Brothers in Red Deerm Alberta, Canada, who are A-car record holders with their '68 Hemi Barracuda. They installed a massaged Indy intake and single Holley 1150 cfm Dominator, and fine-tuned the oil system and rocker arm oiling and found 787 dyno proven horsepower between 6,500-6,800 rpm, with about 650lb/ft of torque between 3,000-3,500 rpm. "It will hold 600 lb/ft to six grand, then it drifts off a bit," said Greg. A beast this big gets hungry, so Nathan custom built a 27 gallon fuel cell to hold its meals.


Challenger Burning RubberHaving this power is one thing, getting it to the rear tire is another. A steel McLeod dual disc 10-inch clutch with a hydraulic throwout bearing is used to get the power through a Hurst-shifted Doug Nash 5-speed with a 1:1 final gear ratio.
     Since Completing their project, the Mace brothers have started their own businesses, which has left them little time to enjoy the fruits of their labor.