Failure is a beautiful thing. As crazy as that sounds, history doesn’t lie. A curious pharmacist whipped up Coke as a cure for headaches, a Kodak engineer accidently invented superglue while designing a plastic gun sight lens, and Play-Doh was originally marketed as a cleaning paste. Granted no one aspires to suck, but sometimes failure can lead to greatness. Jon Clark’s 1968 Plymouth Valiant is a perfect example. Despite packing 528 ci of aluminum big-block fury in a teeny-weeny A-Body—the smallest in fact—Jon insists that the end product is an utter failure. That’s because what was supposed to be a simple, low-buck build got out of hand with a full Pro Touring suspension, a six-speed stick, and paint that’s way too nice for a humble A-Body. While it’s understandable to be disappointed when a finished project car deviates from your original vision, in the walk of Pro Touring machines, it’s one of the best damn failures you’ll ever see.

Like most 40-somethings from Michigan, Jon’s been lusting after muscle cars his entire life. He got a job pumping gas before he could drive, and worked as a line mechanic at dealerships during his formative years. “All I’ve done since childhood is eat, sleep, and breathe cars. I love the smell of gas,” he quips. As you might expect from an A-Body owner, Jon’s mad love of Mopars runs deep, having owned oddball rides such as a Dodge A100 van and a D100 pickup. His passion for Pentastars led to a gig as the head of Mopar Performance, which he ran for 11 years before becoming an independent consultant.

During Jon’s time at Mopar Performance, he met some bad influences that ultimately culminated into the cash-sucking Valiant project. “I started hanging out with Bill Reilly from Reilly Motorsports and Matt Delaney from Delaney Auto Design, and we’ve all become good friends over the years. Bill was building a ’68 Dart with a 528 Hemi, so I thought it would be cool to build a ’68 Valiant with a 528 Wedge motor as a cousin car,” Jon explains. “Unfortunately for Bill, he didn’t know I had my eyes set on the clean six-cylinder, two-door-post Valiant sitting in the corner of his shop. I talked him into selling it to me, and he outfitted it with a complete four-link, K-member, and front suspension from the RMS catalog.”

So far, the project was on track. “The idea was to see how badass we could make the thing while keeping the car as simple as possible, and changing as little as possible. Valiants are simple cars, so when you make them too complicated, it’s like your parents wearing leather pants,” Jon chuckles. The original plan was dropping in a late-model EFI Hemi and an overdrive trans in a good-handling package that anyone could build at home, but Jon got too power hungry. “While researching parts for my 528 build, Edelbrock released its brand-new Victor Max Wedge aluminum raised-runner cylinder heads. I fell in love with the idea of having such new technology in such an old engine platform, and that led to building the motor around an aluminum block.”

To give the big-block the bark to match its cubic inches, Jon hooked up with Ray Barton to build a max-effort wedge. The World Products aluminum block got bored to 4.500 inches, then stuffed with a 4.150-inch forged crank, billet rods, and JE forged pistons. Barton then ported the cylinder heads, and matched them up with an Edelbrock intake manifold, a custom COMP hydraulic roller cam, and a Holley EFI system. The result is a stout 700 hp in a perfectly street-friendly package. Backing up all that big-block torque is a Tremec six-speed manual trans, and a Chrysler 8.75-inch rearend fortified with Moser guts.