Tooth Jerker - Jason Digby- This big power Mopar will yank the pearly whites right out of your mouth

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Story & Photos: Wes Taylor

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ith all the technology poured into today’s drag racing world, why would anyone even think about using technology dating back many decades, if not back to the horse and buggy?

Jason Digby, founder of Leafspring Nations, that’s who! When it comes to clocking up wins, Jason just enjoys gettin’ things done old school!

Owned by Digby and driven by Lyle Barnett, the “Tooth Jerker” 1969 Dodge Dart mixes high tech turbocharged power with some solid leaf spring technology. Jason also runs a prominent company in the industry, Mag’s Fab Worx, which performed a larger portion of the Dart’s build.

Many RPM readers along with drag racers worldwide have heard the name Lyle Barnett.

He’s known as a competitive drag racer who has run in several top tier classes. Most will also know the riveting story of how Lyle almost lost his life in a very severe crash that resulted in a fire that burned most of his body. Barnett didn’t give up, though, and when he wanted to get back

Chris and Trish Biro

118mm of Precision turbo goodness peers its way from the center of the carbon front end.

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out on the dragstrip, Jason had to have him onboard with the Tooth Jerker Dart.

Digby originally bought the Dart as a streetcar and he kept it relatively mild, but the time came when he wanted more, and the Dart was a more than willing candidate.

The reputation of Dodge’s big block wedge motor speaks for itself, however, in more recent years builders and tuners have found that not only do they make power and hold together when built with the right parts, but they love boost!

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The reputation of Dodge’s big block wedge motor speaks for itself...

With the front end off, the symmetrical tube work gives the Dart an almost humanlike look, as if it has a moustache.

The 440 block that came in the car remains, but pretty much everything else has been replaced. All machine work was done at Harrell Engine and Dyno (HED) and the rotating assembly consists of a HED machined forged crank, R&R rods, and custom Ross pistons pushing the cubic inches to 547ci. Pete Harrell has many tricks up his sleeve when it comes to engine building and, due to the competitive nature of racing,

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much of that knowledge is closely guarded, including the exact compression ratio and cam specs for this mill.

Harrell ported a set of RMC billet cylinder heads, fitted them with Victory valves and studded them in place. A set of 1.8 ratio T&D steel roller rockers were also used and the intake manifold is a custom one-off de-

sign made in-house, as well.

The owner of Customs by Bigun, Eric Yost, built the entire turbo system, including the massive 2 ¾ inch headers, hot and cold side, plumbing for the wastegate and the downpipe. The design is based on a 118mm Precision Turbo and Engine turbocharger paired with a JGS wastegate. Bigun also

Eric “Bigun” Yost has his signature work in all areas of the car; all of the turbo system fabrication work is from Customs by Bigun.

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“G Spot” sensors paired with Rife sensors help keep the nose of the Dart planted.

TBM Brakes sport their signature lightweight rotor design on all four corners.

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worked with Digby’s shop, Mags Fab Worx, to build the custom certified cage. Two sets of Billet Atomizer injectors, the first set being 850’s, while the second set is 225lb/min, and Aeromotive pumps supply them. A Holley EFI system controls everything with precision thanks to tuning by, you guessed it, Pete Harrell.

Backing the wicked wedge is a tried and true Turbo 400 transmission built by Proformance Racing Transmissions and a Greg Slack converter pairs the two together. A custom carbon fiber driveshaft connects power to a complete

The one-off fabricated intake manifold pairs nicely with HED machined valve covers

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fabricated Moser rear end stuffed with Strange Engineering axles. Suspending the rear diff is, of course, leaf springs! Sure, we know the setup is based on tech from 1969, but why mess with success. With the help of race quality springs, Smith Racecraft Assassin traction bars, a pair of Menscer Motorsports shocks along with chassis and suspension tuning guru Eric Yost, they have no reason to change it, mostly because they continue to run at the front of the pack. Up front, tubular control arms with Santhuff struts and rack and pinion steering keep things low and straight.

All of the electronics are neatly placed on a fabricated panel to the right of the driver.

A Large Holley LCD dash sits behind a Motion Raceworks steering wheel. www.rpmmag.com

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Moser’s M9 rear end provides a near indestructible link between the horsepower and the tires

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Beadlocked RC Components rear wheels keep the Mickey Thompson radials from turning on them under the punishing power the boosted wedge dishes out.

The Dart has decals all over it, but the trunk showcases everyone who is involved with the car.

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Jason Digby/Lyle Barnett 1969 Dodge Dart Radial Tire Grudge/Outlaw Car

Engine:

Chrysler Wedge 440, now 547 inches.

Bore/Stroke: 4.500/4.125 Crankshaft: HED custom grind Pistons: Ross custom Connecting rods: R&R Compression ratio: top secret Engine built by: Pete Harrell. Harrell Engine & Dyno (HED) Mooresville, NC Camshaft make: HED custom grind solid.

Duration @ .050 in/ex: top secret Lift @ .050 in/ex: top secret LSA: top secret Cylinder heads make/type: Custom RMC billet heads, Machine work: finish machining done in house at HED Intake valves make/size: Victory, top secret Exhaust valves make/size: Victory, top secret Rocker arms: T&D, steel 1.8 ratio.

Air & Fuel:

VCM: Holley EFI Engine tuner: Pete Harrell Injector size: Billet Atomizer 850’s and 225’s Pump(s): Aeromotive Intake manifold: Custom Throttle body make/size: Wilson, big Mass air meter/Map Sensor: Holley Ignition box: Holley

Power Adder:

Turbocharger System: Customs by Bigun Turbocharger Model: PTE 118mm Blow Off Valve: PTE Wastegate: JGS Boost: All of it Intercooler: none Hot side piping size: 5” Cold side piping size: 4” Downpipe: 2.75

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Transmission:

Type: Turbo 400 Converter: Greg Slack, Converter Design Specialities Shifter: M&M Driveshaft: Carbon Fiber Trans built by: Proformance Racing Transmissions

Chassis:

Back half rear, tube chassis front.

Front upper/lower control arms: Custom tubular Front shocks/struts: Santhuff Rear: Leaf Springs Smith Racecraft Assassin Bars, Menscer shocks.

Performance:

Best 1/8 mile ET: 4.10 MPH: 186 60ft. time: 1.09 Horsepower: 3000ish

Miscellaneous:

Coil: MSD Distributor: none Wires: Scott Wires Plugs: NGK Headers: Customs by Bigun, 2.75” Roll bar/cage: MAG’s Fab Worx/ Customs by Bigun Gauges: Holley EFI Dash Carbon fiber front end and doors TBM Brakes RC Components wheels, Mickey Thompson tires.

Thanks to all of our friends, partners, and sponsors who’ve spent countless hours helping us achieve what we have thus far. With Lyle driving, we plan to break into the 3s in 2021 while doin’ it old school, on leafspings!

Driver Lyle Barnett with Jason Digby’s Tooth Jerker Dart.

As you might expect, the Digby Dart looks much more menacing than it’s fairly mild mannered offthe-showroom-floor look. Originally it was Canary yellow, but after installing a carbon fiber front end and doors, the color was swapped out for the much more intimidating black. The Dart sticks to its original roots, though, with a “GT Sport” rally stripe on the rear and GTS badges on the front fenders.

Polishing off its low stance, the Tooth Jerker sits on 15 inch RC Components wheels, sporting Mickey Thompson 26 inch front runners and Mickey 275 radials to meet class

rules outback. TBM brakes stare back at you through the wheels with their signature lightweight rotor design while a Stroud parachute hangs off the rear, making sure things get slowed up in a hurry after a pass.

Inside the cockpit, through the maze of cage bars, Spartan best describes what you see. All the essentials are there and not much more. A Holley dash sits in front of a Motion Raceworks steering wheel. Where the passenger side of the dash pad used to be, Eric fabbed up an entire electronics panel to ensure they could quickly get to things for maintenance and parts swaps between

rounds. Jason is adamant about safety gear; a Firerade suppression system was installed along with the SFI approved harnesses and seat. Rife Sensors help control tunable actions the Dart experiences while on a pass, So far, at full tilt, the estimated power to the ground is approximately 3000whp on “all the boost”. At class weight, the Dart punished the 8th mile cutting a 1.09 sixty-foot while coming out the back door at 186mph in 4.10 seconds, and watch for them to break into the 3-second range this season. That’s insane, don’t ya think?

Especially for a car riding on horse and buggy technology!

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