Home-built racing specials were popular in American sports car racing during the 1950s and 1960s, as they were a more affordable alternative to the costly European imports. The ingenuity and creative engineering of the builders of these home-grown specials were often very successful in the smallest-displacement classes, F, G, and H modified. Power was derived from small production engines like Porsche, Fiat, Crosley, Panhard, and Saab. The wide range of specials produced included some basic designs to high evolved competitive machines.
Curtis Thews was a mechanic for Studebaker in South Bend, Indiana prior to opening his own Volkswagen and Porsche franchise. He was an avid racing in SCCA production class competition and even built a front-engined Crosley-powered H/Modified. An opportunity presented itself by having access to Porsche's racing parts inventory and the urge was too much to deny. He began in 1963 creating a small-bore sports-racer with a Porsche powerplant and a mid-engine setup like the 550 Spyders.
Thews started with the welded-up sheet steel perimeter from a DKW Junior. The DKW Junior had a front-wheel drive setup with inboard brakes. It was strong and lightweight. After Thews made modifications, the wheelbase measured 87-inches. It was given round tubing for a rollbar and front battery support, and a new rear sub-frame to support an engine and transaxle. Most of the front suspension remained DKW, incorporating Porsche 356 brakes. The rear suspension setup was mostly sourced from a 356, and given Volkswagen Transporter brakes. Centaur, a small racing shop in Detroit, supplied the fiberglass body. Thews then bought a pair of brand-new 1600cc Porsche Type 692 four-cam Carrera engines in Texas.
H/Modified rules stated engine displacement size must be under 850cc. To comply with these rules, Thews made one of his Carrera fours into a Carrera two by removing one pair of opposing pistons and rods. He machined special caps to block the appropriate oil passengers in the crankshaft, blanking off the empty cylinders, removing lobes from two camshafts, and the no-longer-necessary valve train parts. The result was a very effective four-cam twin of just under 800cc. When Thews wanted to race in F Class, the 800cc unit could easily be swapped out and replaced with the 1600cc four-cylinder unit.
The TM Special was raced with great success across the Midwest, though it proved too heavy to be a consistent winner in H/Modified. After retiring from this form of racing, it was entered in autocross events after a six-cylinder 911 engine was installed.
In 2004, the car was sold to a West Coast Collector, who in turn sold it to the current owner. The car was then treated to a professional restoration. It was given new Koni shocks in the front, with Koni coil-overs in the rear. A new, stronger rollbar was fabricated.
Currently, the TM Special is powered by a flat-four engine incorporating a 912 case and heads, Shasta pistons, and a Neutek cam. It produces around 100 horsepower which is more than enough for the light weight vehicle (nearly a thousand pounds).
In 2011, the car was offered for sale at the Quail Lodge auction presented by Bonhams. It was estimated to sell for $75,000 - $95,000 but did not receive a high bid needed to satisfy its reserve. It would leave the auction unsold.