1971 Dodge Charger R/T Hellcat

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1971 Dodge Charger R/T Hellcat

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A "Hellcrate" transplant into a '71 Charger R/T delivers pressurized performance
https://www.hemmings.com/stories/article/super-charger
When it comes to surprisingly rare muscle cars, the 1971 Charger R/T doesn't always come to mind, but only 3,118 were built. For comparison, Ford built just about 36,500 Mustang Mach 1 models that year. So, yeah, the '71 Charger R/T represents a thin slice of the Mopar muscle pie—and only 30 of them were factory sunroof cars. Only 30. Alberta collector and dealer Peter Swainson owns four of them, including one that was originally Tawny Gold and had been brought to Canada from California, but sat for years when the previous owner failed to pull the trigger on the restoration.

Peter had his own grand plans for the car, but there were a couple of important details that held it back.

"Well, it didn't have a build sheet and the original engine and transmission were long gone," he says. "It was still a very unique car, but what to do with it was a dilemma."

Peter was already working with Detroit-area Mopar specialist Dave Dudek, whose shop, Dave Dudek Muscle Cars, had already wrenched on a number of projects for him, including a B5 Blue '69 Daytona. Dave was on deck to restore another B5 Blue Daytona for his Canadian client, but after he got it running well enough to show it in unrestored condition at the Muscle Car and Corvette Nationals, fellow Moparians and other muscle car fans pleaded with them to stand down the block sanders and leave it unrestored. Peter agreed… well, for the time being, at least. Besides, there was already another B5 Blue Daytona in his barn in Red Deer, so he was covered on the restored wing car front.

When it came to the '71 Charger, Peter and Dave agreed that, without the original drivetrain and supporting paperwork, a concours-level full restoration probably wasn't warranted.

"Numbers mean everything in the Mopar world, and the car simply didn't have them," Dave says. "Building a restomod with it seemed like the logical thing to do. Peter already had several great restored, show-quality cars, but this one would be for driving."

The original vision was to nestle a modern 392 "Scat Pack" crate engine in the rare B-body. It progressed as far as buying the engine and a set of swap headers, but Peter's other projects took precedence at Dave's shop, and the Charger collected dust in the corner until a couple of years ago. But then, without that Daytona to restore, it leaped to the top of the project list.

The project's delay had an unanticipated, but fortuitous, consequence: Mopar Performance released the supercharged, 707-horsepower Hellcat crate engine package known as the "Hellcrate." It wasn't available when Peter and Dave initially planned on using the 392 engine.

"It made all the difference in deciding which way to go with the project," says Peter. "And when we finally decided on the Hellcrate, I couldn't wait for the car to get finished."

SWAP STUFF Unlike mainstream LS engine conversions, where virtually every component from the engine mounts to direct-replacement gauge clusters are available for bolt-in installations, the aftermarket support for modern Hemi swaps is still comparatively thin— particularly with the Hellcat engine.

"The engine mounts are out there, along with some oil pans, headers, and more, but the Hellcat has a unique oil pan and we couldn't find direct-replacement headers for the 1971-andup B-bodies," says Dave. "There are three computers with the Mopar control system, too, which requires plenty of wiring."

Dave modified a Milodon swap oil pan for other Hemi conversions to fit the Hellcat engine, while the headers originally purchased for the 392 swap were sliced, diced, and reconfigured to fit the '71 Charger's engine bay. All three modules for the control system were tucked out of sight under the dashboard, with almost all of the wiring running discreetly through the inside of the fenders—a feat that Dave says was among the most challenging chores of the project. Well, that and the DIY engineering required to make all the gauges.

"There aren't plug-and-play options for the Hemi system, like there are for the LS swaps," says Dave. "We had to get creative to get the old-school analog gauges to work with an electronically controlled drivetrain."

For the oil pressure and engine temperature gauges, Dave simply inserted mechanical senders and ran them independently of the engine control system. He did, however, have to tap into the control harness to make the tachometer work. It required 16 splices.

"That was kind of a nightmare," he says. "It works just fine, but it's not something I'd want to do again soon."

The speedometer, however, was a cinch. That's because instead of a modern electronically-controlled overdrive transmission, the Hellcrate is backed by a Passon Performance five-speed manual gearbox based on Chrysler's own stalwart A-833 "Hemi" fourspeed, so the original speedometer cable plugged right into it. The additional overdrive top gear ratio is 0.70:1, which turns any vehicle with it into a more comfortable highway cruiser.

It's a significant upgrade for a number of reasons, not the least of which is it fits the transmission tunnel without modifications. That's been the traditional challenge for adding later overdrive automatics and other transmissions to many muscle car-era Mopars. In fact, the Passon Performance transmission not only slips into the tunnel like a stock A-833, it uses the stock crossmember and mount, and has proven to be a great contemporary complement to the Hellcat engine.

There was more to packaging the supercharged powertrain than literally meets the eye, too. With the hood up, there is a pair of neatly trimmed closeout panels in the space between the chrome front bumper and the radiator. Beneath them are the heat exchangers, coolant pumps, and plumbing for the blower's intercooling system.

"There are a lot of supporting components for the supercharger," says Dave. "Fortunately, there's a lot of room in the Charger's nose, but it was a challenge to keep it all clean and uncluttered."

He succeeded. The engine compartment looks exceptionally tidy, without the mass of wiring expected with a modern, electronically controlled engine.
"It looks like the engine was an original factory option," says Peter. "The execution is perfect."

There's one more thing to note about the engine's installation: The air intakes using the inboard headlamp locations are a nod to the production Hellcat models, a nice detail.

COILOVERS AND MORE The Charger's modern powerplant is matched with equally contemporary coilover front and rear suspension systems, from Reilly Motorsports. In the front, it's the AlterKtion setup that includes a rack-and-pinion steering system, and at the rear it's a Street-Lynx triangulated four-bar system used with a Dana rear axle. The car rolls on Year One's modern 17-inch interpretations of the Magnum 500 wheel design.

When it comes to the Charger's exterior color, the original Tawny Gold was changed to Gunmetal Grey, which also looks like a contemporary update in an age of charcoal and silver metallic new vehicles, but it's actually a factory 1971 Dodge color.

"It was a great choice, because it is simultaneously vintage and modern," says Peter. "That's exactly what this car is all about."

The interior was left largely stock-appearing, except for some comparatively discreet "SRT" stitching on the door panels, but the leather-trimmed seats are what would normally be found in the plusher SE model. Nevertheless, the upholstery, instruments, steering wheel and Pistol-Grip shifter are all straight out of 1971. The only deviation is an OBD port for the engine control system, mounted below the dashboard.

"In 1971, a car like this with 700-plus horsepower would have been a race car," says Dave. "I've driven heavier production Hellcat cars that ran in the high-10s, so I think with the right tires and suspension tuning, this one could run 10.30s or even better. But it also starts right up when it's only 5 degrees outside, and you could drive it across the country after it gave you a 10-second timeslip. That's an incredible balance of performance."

Peter echoes those sentiments. "The car is a total package, without compromises," he says. "From the sound of the supercharger to the fact that all of its performance is contained within the great lines of the 1971 Charger bodywork, it's the best of both worlds."

Dave and Peter are spot-on in their respective assessments. The Hellcat engine is a touchstone performance enabler that is sure to grow in popularity, as conversion support also continues to increase—and the same goes for the Passon Performance five-speed transmission.

Together, they've elevated what would have been a standard restoration to higher levels of involvement, enjoyment and relevance. And believe the shriek of the twin-screw supercharger at wide-open throttle, which sounds like it's going to open a black hole of airflow in front of those headlamp intakes, is a sensory experience that far outweighs another concours blue ribbon.

OWNER'S VIEW Twenty years ago, the 1971-and-later B-bodies were cars I didn't much care for, but things changed. I've grown to appreciate their sleek design and muscular shoulders. They were really successful on the racetrack, too, which I think makes a high-performance restomod like this one all the more appropriate. I'm planning to really put some miles on this and make use of all the Hellcat engine has to offer. —Peter Swainson

SPECIFICATIONS 1971 DODGE CHARGER R/T

ENGINE
Block type..........................................Gen III Chrysler Hemi V-8; cast iron
Cylinder heads.....................................Gen III Chrysler Hemi; aluminum
Displacement......................................376-cu.in. (6.2-liter)
Bore x stroke...................................... 4.09 x 3.58 in
Compression ratio................................ 9.5:1
Pistons..............................................Forged aluminum with friction-coated skirts
Connecting rods...................................Forged steel
Crankshaft.........................................Forged steel with induction hardened journals
Horsepower @ rpm............................... 707 @ 6,00
Torque @ rpm.....................................650 @ 4,800
Camshaft type................................... Hydraulic roller with phasing
Duration...........................................286/288 degrees (at 0.050)
Lift.................................................561/.551-in
Lobe separation angle .......................... 120.5 degrees
Valvetrain......................................... Hydraulic roller
Induction system.................................Chrysler / IHI 2.4-liter twin-screw supercharger with 11.6 lb max boost and electronically controlled bypass valve; 92-mm throttle body;high-pressure-fuel pump mounted in modified original fuel tank; 68-lb/h fuel injectors
Lubrication system...............................Chrysler gerotor-type oil pump with steel gears
Ignition system................................... Chrysler individual coil-on plug
Exhaust system....................................Headers with custom 3-in stainless exhaust system (includes X-pipe)
Original engine....................................Chrysler 440-cu.in. V-8

TRANSMISSION
Type................................................Passon Performance "A-855" five-speed manual
Ratios.... 1st/2.64:1 … 2nd/1.92:1 … 3rd/1.40:1 … 4th/1.00:1 … 5th/0.70:1 … Reverse/2.58:1

DIFFERENTIAL
Type................................Dana 60 with limited-slip differential and hardened axle shafts
Ratio...............................3.54:1

STEERING
Type................................................. Power-assisted rack-and-pinion
Ratio.................................................12.7:1
Turns, lock-to-lock................................ 2.75 (est.)
Turning circle.......................................38 ft (est.)

BRAKES
Type..................................Wilwood four-wheel disc, Hydratech hydroboost power assist
Front.................................11.75-in drilled/slotted rotors, four-piston calipers
Rear................................. 11-in drilled/slotted rotors, four-piston calipers

SUSPENSION
Front................................. Reilly Motorsports AlterKtion coilover conversion with twin-tube adjustable dampers, 1.25-in anti-roll bar
Rear...................................Reilly Motorsports Street-Lynx triangulated four-bar with coilovers with double-adjustable shocks

WHEELS AND TIRES
Wheels................................ Year One Magnum-style Front/Rear: 17 x 9 in
Tires...................................Nitto NT450 Front: 245/50R17 Rear: 275/50R17
Another great Hellcat swap into some old Mopar iron! Very nice!

#1971 #Dodge #Charger #DodgeCharger #1971DodgeCharger #Hellcat #HEMI #Mopar
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