A motor trader from Mannheim in Germany, the balding Helfrich enjoyed considerable success in the early fifties and was one of Germany's best 'lesser-known' drivers.
He took a win at Hockenheim in 1950 driving a Veritas and, over the next year or so, had some excellent results. This brought him to the attention of the works Mecedes-Benz team and an invitation to race one of their three 300SLs with Niedermayr at Le Mans. Together they took a fine second place behind the Riess/Lang sister car.
In 1953 he raced a single-seater Veritas and won the German Formula 2 championship as well as helping to develop the little Borgward sports car. Theo and Gunther Bechem brought the potent little machine into third place overall, and easily won the 750-1500 cc class. Although Helfrich handled Klenk's car in the 1954 German Grand Prix, the rule changes had swept away Formula 2 in favour of the new 2.5-litre F1.
Thus in 1954 Theo purchased an F3 Cooper and proceeded to win in hill-climbs and minor races, taking seven wins in ten outings that year. Perhaps his most notable performance, though, was second to Moss in that year's Eifelrennen on 23rd May. He also took F3 wins at Leipzig, Dresden, Halle Salle and at the Sachsenring.
He continued with the Cooper for two more years, taking two seconds and a third in 1955.
Purchasing a 1500 cc Porsche Spyder, Helfrich raced on for a couple more years, taking fifth place at Rouen in 1956.