The Ultimate Challenger

Slide Show

Bob Motz's 1970 Challenger

“I knew it had to have a big engine…” says Bob Motz of his 1970 Challenger R/T, “…and I wanted it to be different. I’ve seen my fair share of Chevy 350s and ’Cudas. They’re nice, but I wanted to have the car that you don’t see at every show and it had to be done right,” Bob continues. Mission accomplished. 

You’re looking at Bob’s final creation: an award winning, done-to-spec show car with an all-out Pro Streeter attitude to back up those pretty looks. From the built Hemi and super tough FAB9 rear end to the paint job, custom wheels, and gold leaf detail, every step of this build was influenced by Bob’s experiences as an enthusiast, and his appreciation of classic musclecars.

Bob’s love of big engines and fast cars started a little more than four decades ago, when he was at a drive-in and someone in a beefed up musclecar peeled out, lit ’em up, and shook the windows of the car he was in. He was instantly hooked.

Over the next few decades, he spent a lot of time at the dragstrip, building and racing cars, and rubbing elbows with legends of the sport. When the Hemi came out and dominated the track, Bob was there. He witnessed Sox and Martin in their heyday, and it was a great time to be a Mopar fan. In fact, the trailer that Bob bought to take this Challenger to those far away car shows belonged to Ronnie Sox. “I told him I’d buy it if he autographed it,” Bob says as he shows off the big signature on the cabinets inside. 

It’s no surprise, then, that Bob knew the “really big engine” for this project would be the ultimate Hemi, but first he had to find a car worthy of such a powerplant. After about six months of searching, he found a rusty old Challenger that needed an engine and some TLC. He completely disassembled the car and sent it to Rocky’s Auto Body for major restoration and repair. For this old school hot rodder, it was very important that the car remained true to its original form.

“Too many people change these cars so much that they don’t even have the same lines as the originals. That’s not my style. It looked great then and it looks great now,” Bob says. “Chrysler did a fine job, don’t mess with a good thing.”

The custom blend PPG Candy Apple Red bottom and Black Cherry top highlight the bodylines that Bob’s so fond of and he had the paint scheme on the hood flip-flopped (black on the sides and body color up the middle) from the usual look to help show off the hood’s attitude. Before Rocky’s got to the clear coat, Bob had local artist Dave Knepper add a custom touch that makes this show car “done right.” A stripe of variegated gold leaf separates the two colors around the body and highlights the detail on the hood and air cleaner. In the sun, that 550 Hemi graphic on the hood lights up like a neon sign in Vegas.

Under that fancy hood, there’s an all-aluminum Keith Black Hemi that’s been worked over by Koffel’s Place for a window-shaking 810 hp and 745 ft.-lbs. of torque. That’s without the nitrous. Add a shot from the NOS Pro Fogger 2 system and you’re looking at approximately 1,300 horses. The Hemi’s stuffed with all kinds of go-fast goodies and it’s topped by an air cleaner that Bob fabbed up from a spare sheet of metal. “I needed something that would clear the hood so I found a piece of sheetmetal and designed this air cleaner,” says Bob. Now that’s some good old-fashioned car guy ingenuity.

Advanced Chassis installed a 12-point chromemoly roll cage, crossmembers, frame supports, and motor mounts. Out back, the Challenger has a custom-fabricated FAB9 rear end, built tough to handle all that power, and to make room for those extra big tires. “It’s not common, and it’s more of a tough Pro Street look than you usually see,” says Bob with a smile. To enhance your view of the Challenger’s back end, Chris Dixon of Wounded Knee Motors cut and customized the car’s rear valance so those tailpipes are tucked up and centered.

With the body and paint, engine, and chassis work done, Bob had the Challenger on the car show scene for about 5 years. One day, he came in second to a car that just shouldn’t have taken place over the Challenger. Bob took a look at his car, and at the winning car, and made a to-do list so that wouldn’t happen again: interior, wheels, AirRide suspension.

Bob got to work, going back and forth with the folks at Boyd Coddington Wheels to design the perfect 10-spoke, race-inspired wheel. The end result is a Pro Streeter-meets-show car design that sets the mood for the entire car.

The interior went from mostly stock to show-winning style, courtesy of Paul Atkins Interiors. Just like the car’s bodylines, Bob wanted to keep the inside as clean and simple as possible—no TV screens or in-your-face technology—just the elements necessary for the cockpit of a racecar, with an extra touch of class. Underneath that gorgeous Austrian leather is a pair of Summit Sport seats, and the Simpson 5-point camlock harnesses remind you that you’re looking at an 810 hp street machine.

Remember how Bob left the Challenger’s bodylines alone? Well that paid off because in 2007, Chrysler invited Bob and his Challenger to display in the booth at the SEMA Show in Las Vegas, to kick off the 2008 Challenger. “To see this car sitting next to the new Challenger was really something,” says Bob.

Bob and the Challenger have been taking the car show circuit by storm. The list of awards goes on for miles with dozens of Best in Class awards from ISCA-judged shows across the Midwest, but they don’t stop there. At the 2008 Mopars at the Strip in Las Vegas, NV, Bob took home the prestigious World’s Ultimate Mopar award sponsored by Barrett-Jackson, plus Best of Show, and the Mopar Muscle Editor’s Choice Award. Well done Bob.

Photography By Kenneth Stidwill
Art Direction By David Lewis
Story By Jen Hanna

FAST SPECS

Chassis
Frame: Stock with 12-point 4130 chromemoly roll cage, aluminum tubs, custom crossmembers and frame supports
Rear End: Chris Alston’s Chassisworks FAB9 with Strange axles and aluminum third member (Jet-Hot coated), Detroit Locker differential, Strange Pro 4.11 gears, Bullitt Yoke
Suspension: Magnumforce 4130 chromemoly tubular K-member suspension, 4-link rear suspension, Air Ride Technologies ShockWave system
Brakes: Wilwood Pro Series Disc Brakes with polished 4-piston calipers
Wheels and Tires: Custom Boyd Coddington (18" front, 20" rear) wheels wrapped in Mickey Thompson Sportsman S/R tires (26 x 6.00R18LT fronts and 31 x 18.00R20LT rear)

Engine and Transmission
Engine: 550 cubic inch Keith Black aluminum Hemi, bored with a 4.500” bore
Engine By: Koffel’s Place
Valvetrain: ATI Super Damper, Eagle Specialties 4340 crank, Eagle Specialties ESP H-Beam connecting rods with ARP 2000 rod bolts, Venolia pistons, Chrysler aluminum cylinder heads (machined/ported by Total Flow), Crane roller cam, KPI chromemoly pushrods, KPI rollmaster timing chain set
Induction: Holley 4500 4-barrel Dominator carb, Indy Cylinder Head 426 intake manifold, custom air cleaner (owner designed), NOS Pro Shot Fogger 2 nitrous system
Exhaust: Custom stainless steel headers with 28” long primaries/4" collectors, custom stainless steel exhaust system, Summit Polished Stainless Steel mufflers
Exhaust By: Chris Dixon, Wounded Knee Motors
Transmission: TKO600 Tremec 5-speed, Lakewood bellhousing
Other Items: Be Cool Crossflow 1,050 hp radiator with custom shroud, dual chrome electric fans, 15 gallon aluminum fuel cell, mini starter, Optima Red Top battery, Powermaster chrome 100 amp alternator, Summit hood pin kit

Body
Modifications: Restored and straightened body, rear valance modified for tailpipes, LizardSkin coated
Valance Modified By: Chris Dixon, Wounded Knee Motors
Paint Color: PPG Custom Blend Candy Apple on bottom, Black Cherry top 
Body and Paint By: Rocky’s Auto Body
Striping and Accents: Variegated gold leaf, hand applied by Dave Knepper

Interior
Upholstery: Austrian leather seats/door panels Ultra Suede headliner, Mercedes carpet
Interior Components: Summit Sport Seats with Simpson 5-point camlock harnesses, Jerry Bickell carbon fiber roll bar covers, Billet Specialties Dragster Half Wrap steering wheel, Ididit steering column, Auto Meter Cobalt Series Gauges, Alpine stereo, Billet Specialties rearview mirror, Pistol Grip shifter, Paul Atkins handles, cranks, foot pedals 
Interior By: Paul Atkins

Special Thanks To: My friend Lance