THE AERODYNAMICS OF A BARN DOOR
ROGER JOHNS’ 1947 FARM TRUCK DOES SOME SERIOUS HAULIN’
Roger Johns’ 1947 Farm Truck Does Some Serious Haulin’
THE ONLY HAULING ROGER JOHNS’ CHOPPED ’47 3100 SERIES CHEVROLET ½-TON DOES THESE DAYS IS THROUGH THE QUARTER-MILE, AND HE DOES IT TO THE TUNE OF 9.34-148. NAMED HOODLUM, THIS SLIME GREEN (IN THE OWNER’S WORDS) ’47 HAS THE AERODYNAMICS OF A BARN DOOR, BUT IT HURTS FEELINGS ON A REGULAR BASIS.
Built almost entirely by Johns’ company, RJ Motorsports, Hoodlum features a double-rail DOM round tube 115-inch wheelbase chassis. The rear suspension consists of an RJ Motorsports 4-link setup working in conjunction with a pair of Aldan QA1 double-adjustable #150 coil-over rear shocks. A 4.57:1 spool (with MW aluminum center section and REM polished MW gears) spins inside an MW 9-inch Ford housing and features MW gun-drilled 33-spline axles. The truck stops via a pair of four-piston Wilwood rear disc brakes. Up front you’ll find Art Morrison upper and lower tubular A-arm suspension deploying AM Mustang II front spindles, QA1 coilover front shocks, Wilwood four-piston front disc brakes, a 1 ½-inch AE anti-sway bar and AM Mustang-II-type rack-and-pinion steering gear. Wheels and tires consist of a set of black PlastiDipped 15x3.5-inch Weld Pro Star II front, and 15x12-inch Weld Pro Star II modular rear wheels rolling on Goodyear racing rubber.
Power is provided by a Brand Racing Engines (Mustang, Oklahoma) 413-ci World Products Motown II small-block Chevy sporting a 3.75-inch Calles crank, 6-inch GRP aluminum connecting rods and a set of Total-Seal-equipped 16:1compression Diamond Racing combustion-chamber-matched pistons. Power doesn’t stop there, though, a proprietary grind big inch BRE solid roller cam, Cloyes double roller timing chain, King engine bearings, ARP fasteners, CVR billet oil pump and 7-quart Milodon oil pan circulating Royal Purple XPR 5W/30 oil round things out.
The engine is cooled via CSR electric water pump and a Griffin four-core aluminum radiator.
A set of RFD custom-ported aluminum alloy 15-degree cylinder heads feature a 2.223inch-diameter intake and 1.6-inch-diameter Manley titanium valves. PAC custom springs with Manley retainers, a set of 1.6/1.7-ratio T&D custom offset rocker arms, Manley push rods and .903 Crower extreme duty lifters are protected by a set of tall deck Johnson Fabrication sheet-metal valve covers. Induction is handled by a Self Racing Engines customfabricated sheet-metal ram intake sporting a Ron’s Fuel Injection Terminator throttle body with air intake tubes set into the headlight buckets and a set of #35 Ron’s Terminator mechanical fuel injectors.
Ignition duties have been allocated to an MSD Pro Billet distributor and crank trigger firing a set of NGK spark plugs.
Exhaust is expelled by a set of HPC thermal-coated Lemons
1 7⁄8- to 1 5⁄8-inch-diameter stepped headers with adjustable 4-inch collectors.
Backing it all up is a Wilson Racing Transmissions
(Oklahoma City, Oklahoma) two-speed Powerglide sporting a REID explosion-proof case and Wilson 1.98:1 first gear. Hoodlum also features a 168-tooth flex plate, Greg Porter Enterprises GPE starter and 8-inchdiameter 6900-stall-speed COAN billet-aluminum converter. The final link in the truck’s power train is a 65-inch-aluminum Denny’s driveshaft.
Johns took 4 inches out of his truck’s roof to help it slip through the air a little easier. He also custom-fabricated the carbonfiber one-piece hood and lightweight pickup bed (notice the lack of a bulkhead and tailgate) and widened the rear fenders to keep those 31.5x15 Goodyears tucked inside the fender wells. Lastly, he sprayed the truck in a custom mix of lime green, which, under the lights at tracks like Tulsa Raceway Park (thanks Cliff Parvin and TRP), contrasts with the black to become slime green. Lastly, Mik’s Artwerks from Oklahoma City is responsible for the graphics.
Inside, Johns’ truck features an NHRA-legal S/G/S/C roll cage, a single Kirkey race seat, Auto Meter instrumentation, Stroud safety equipment, a TCI shifter and wireless RPM Performance data collection system.
ON THE COVER:
Ron Capps captures the crown! Inside Pomona Finals action and new champs.
/Credit for building the Hoodlum’s 413-inch World Products Motown II Chevy small-block goes to Mustang, Oklahoma’s Brand Racing Engines.
/The threequarter rear shot is an angle many competitors get to see. As early Chevrolet race trucks go, this is one of the coolest.
/The interior is strictly business. There’s the NHRA-certified roll cage, Kirkey race seat, Stroud safety harnesses, Auto Meter instrumentation, TCI shifter and stand-alone RPM Performance data collection system.
/With the exception of the drivetrain, the 62-year-old Johns, a successful international sales executive and owner of RJ Motorsports (and member of WFO Drag Trucks), virtually built the Hoodlum from the ground up, including the 115-inch wheelbase mild steel (DOM) dual-rail chassis, preparing the ’47 Chevrolet body right down to paint and final assembly.
/Rear suspension consists of an RJM 4-link and QA1 coil-over-suspended MW Enterprises’ 4.57:1-geared Ford spool. Rear brakes are four-piston Wilwood Engineering units. Wheels and tires are black-painted Weld Pro Star IIs rolling on Goodyear Eagles.
/Out back is a highly modified Chevrolet 3100 series pickup bed sans tailgate and rear bulkhead. The fuel tank is a moon 20-gallon model. A set of late-model Chevy pickup inner wheel wells were moved inboard to house the slicks.