Some cars are strictly his, while others are his and hers. But the best way to describe Margi and Wayne Puffer’s 1970 Duster 340: Theirs.

That’s because while Wayne outlined the modifications that went into it, it was Margi who picked out the car to begin with. “The car was purchased the day we got engaged,” recalls Wayne. “I proposed to her at dinner, and we ended up going to a cruise night.”

At that cruise-in was a Yellow Gold ’70 Duster 340, which caught Margi’s eye first. “She kept coming back to me, and asking me questions, and I kept giving her answers, and she’d go back to the guy who owned it and talk to him...All of a sudden, she says, ‘There’s a car I want to buy.’ I asked which one, and she said ‘The Duster.’ I said, ‘No way!’ and she says, ‘No, really—come over and look at it.”

Wayne continues. “I went over to look at it, and the car was clean. It was originally a Canadian car that ended up in Florida.”

When a deal was finally struck, they got it home and started planning their “Dusteration,” starting with needed work to make it safely drivable. “We had to replace the clutch, the upper and lower control arms, and re-do the brakes,” says Wayne, who had Rick Weissman install Hotchkis’ tubular A-arms.

For the next phase, they considered replacing the 340’s four-barrel with a 6-barrel. Rick Weissman suggested going with an EFI setup instead of carburetors, and they tracked down F&B Throttle Bodies.

Before the EFI—or anything else—went on, Wayne and Margi went to the Mopar Nationals. Armed with a wish list of parts, they came away with plenty. Items like Mancini Racing subframe connectors, and new door panels from Legendary Auto Interiors—whose salesman, per Margi, said this was the first time a wife ever ordered parts and needed her husband’s approval!

During their parts search, Wayne’s friend, Rick Blaha, tipped them off about Muscle Motors’ tent, where a stroker LA small-block was on display. He checked it out, and—once they were home—they ordered a 416-inch stroker from Muscle Motors. Once built, it went to C&S Performance in Butler, Wisconsin, for a pair of Edelbrock aluminum heads and the 6-barrel EFI system they’d planned.

Then, Weissman Automotive installed the stroker fuelie (with FAST’s ECM and tuning) along with Competition Engineering’s Slide-A-Link rear suspension and QA1 shocks all around.

Fast Facts

1970 Plymouth Duster 340
Margi & Wayne Puffer, Germantown, Wisconsin

Mopar Power

Engine: Muscle Motors in Lansing, Michigan, built the 416-inch stroker from an .030-inch overbored 340 block and an Eagle four-inch crankshaft, then added Eagle H-Beam rods and Icon 11.0:1 pistons, a custom-grind Comp Cams roller camshaft and lifters set, fully-ported Edelbrock aluminum heads, and topped it with a 6-Barrel-look EFI system made of three F&B throttle bodies (with FAST modules, computer, and tuning) on a factory 340 Six Barrel intake. The ignition is an MSD system, headers are tti’s, and the mufflers are Flowmaster 44s.
Transmission: Rebuilt 833 four-speed with Hurst Pistol Grip shifter
Rear: 83⁄4 with a Sure Grip differential and 3.91 gears

Sure Grip

Suspension: (Front) Hotchkis tubular A-arms and QA1 adjustable 90/10 shocks (Rear) QA1 adjustable shocks and Competition Engineering’s Slide-A-Link rear suspension
Brakes: Four-wheel discs at each corner replaced the OEM brake system
Wheels/Tires: 17-inch Rocket Racing “Fuel” wheels wear 255/50R17 Kumho “Esta” radials in front and 275/5-R17 M&H Racemaster Drag radials in back.

High Impact

Paint/Body: Original ’70 Duster unibody still wears its original sheetmetal and Yellow Gold acrylic. Grille and headlight bezels are N.O.S., while the rear bumper is from Tri-City Plating in Elizabethton, Tennessee.
Interior: Straight Line Upholstery in Sussex, Wisconsin, restored the cabin and finished the trunk, and Wayne and Margi added a Redline Gauge Works gauge cluster, Grant steering wheel, an AM/FM/MP3 flash drive player mounted in the glovebox, and Wayne’s shop—MJM Ventures in Menominee Falls, Wisconsin—embroidered a Pentastar logo on the back seat.