One of the most significant Mopars in drag racing history is finally crossing the auction block — and it’s not just any old HEMI® car. On Saturday, May 17th, 2025, at Mecum Indy, the legendary 1968 Plymouth Barracuda B029 Prototype — known as “The Mule” — will go under the hammer. This isn’t just a Super Stocker. It’s the Super Stocker — the very prototype Chrysler Engineering used to develop the 1968 HEMI Super Stock Barracuda program.
Originally built as a Formula S 340 small-block car by the Road Test Garage, this engineering mule (Car No. 139) was transformed by the Special Vehicle Department to test-fit the monstrous 7.0-liter (426 cubic-inch) HEMI V8 and work out the kinks for what would become the most feared drag cars of the era. It was an R&D car through and through — a real B029, with prototype blue fiberglass fenders, scooped lift-off hood, 6-cylinder front torsion bars, and all the quirks that came with early Super Stock experimentation.
After testing wrapped, Chrysler was ready to scrap it — until Akron Arlen Vanke stepped in and bought the car for $1. Yes, one dollar. He raced it briefly, then sold it to Tony Suppa, who turned it into the now-famous “Suppa Cuda.” Suppa nearly took home the win at the U.S. Nationals in Indy, losing only to Ron “Zoomo” Mancini in a close race that’s still talked about today.
Eventually, the car was rescued by collector Patrick McGroder and given a faithful restoration back to its early 1968 “Irwindale testing” spec — the same look seen in old Hot Rod Magazine spreads. The restoration was so accurate that it earned a spot in the Chrysler Museum’s performance car display and was later shown off at events like Mopars at the Red Barns, the All HEMI Reunion, and the Nats in Columbus. It even got the spotlight at the U.S. Nationals during the Sox & Martin HEMI Challenge parade lap — a moment topped off by event champ Steve Comella himself saying, “Without this car, none of us would be here today.”
Under the hood? A 426 HEMI V8 personally assembled by Arlen Vanke himself, featuring a cross-ram intake, dual Holley 4-barrels, Hooker headers, and a serious 12.5:1 compression ratio. Power goes through a heavy-duty TorqueFlite 727 automatic to a Dana 60 rear end with Sure Grip. It’s built for straight-line speed, with magnesium front wheels, Goodyear Eagle slicks in the rear, and disc brakes up front with custom adapters to clear the big HEMI valve covers.
Inside, the car has all the lightweight tricks: manual windows with pull-up straps, aluminum seat frames, and a relocated battery in the trunk. But it still carries factory Formula S woodgrain touches and a Hurst Dual Gate shifter to remind you it started life as a street car.
Along with the car comes an incredible collection of documentation, including build and test photos from 1967-68, original engineering correspondence, Bob Tarozzi’s hand-drawn sketches, and a 40-minute audio interview with Vanke detailing the car’s full backstory.
Offered on a Bill of Sale, this is not a street-legal machine — it’s a piece of rolling Super Stock history. A true one-off from Chrysler Engineering, this Barracuda isn’t just rare… it’s the reason SS/AH racing exists. If you’re a HEMI fanatic or a muscle car historian, “The Mule” is the holy grail.
1968 B029 HEMI® Barracuda Prototype Image Gallery:
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