Concept Car of the Week: Dodge M4S PPG Turbo Interceptor (1985)

As a major paint supplier of Detroit's big three, PPG would commission every year a car to be used as a pace car in the Indy Car World Series.

In 1984 Chrysler began the development of a mid-engined, rear-wheel drive car using an experimental powertrain. To avoid the costs of creating a whole new chassis, the M4S is based on a modified Huffaker tubular chassis with full roll cage taken from the Pontiac Fiero IMSA race car, only lengthened to a 100-inch wheelbase. That was the basis for starting the M4S, standing for Mid-engined, 4-cylinder Sport vehicle. All the mechanical and assembly work was the responsibility of a company called SVI (Specialized Vehicle Inc.) who supplied Chrysler for the PPG projects.

Bob Ackerman was the lead designer on the project, creating a fiberglass body that was then fitted onto the chassis. Inspired by race cars like the Porsche 962 GTP, his design features a smooth body with a Kamm tail and integrated rear spoiler, invisible from side view. Its windshield was taken from a Ferrari Berlinetta boxer. Although the final design looks very neat, it was more engineered than styled, with aerodynamic performance the real focus.

Chrysler and PPG were after something exotic to put under the bonnet. Engineers at SVI used a four-cylinder 2.2-liter block from Chrysler as a base and added new Moldex billet crankshafts, Cosworth pistons, Cosworth 16-valve twin-cam head, new fuel injection, and last but not least twin Garrett turbochargers and a huge intercooler. The result was an impressive 440 horsepower and 200bhp per liter. After aero tests, the car did not have enough downforce and a large wing was added at the rear in Daytona style.

Engineers were keen to take the car for speed runs and after changing the wheels and some tweaks to the turbo wastegate, the M4S went all the way to 195mph.

PPG picked the paint color, a metallic brown with mauve Pace Car lettering, matching the wheel centers. When the car was presented to Lee Iacocca, he was smoking a cigar as he looked the car over: "I'll be damned," he said. "Almost 200 miles an hour and pink wheels!"

In 1985 it became the official PPG pace car at all the Indy Car races, but reliability issues meant it didn't make it for the 1986 season. Instead the car was used by Chrysler as a display piece every once in a while at auto shows and events.

From there it became the star of the very cheesy 1986 sci-fi movie called The Wraith. The real car was only used for a few close up shots. All the other scenes featured movie cars, and most of them got wrecked or exploded for our nerdy entertainment.

First seen 1985 INDY racing season
Designer Bob Ackerman
Engine Four-cylinder, 2,200 cc, twin turbo
Power 440 bhp
Top speed 195 mph
Drag coefficient 0.236

Your author, Flavien Dachet, is a UK-based, French-born car designer. You may know him as the purveyor of KarzNshit, a photo blog that if isn't already in your bookmarks, certainly should be.

By Flavien Dachet