Peter Broeker, owner and president of an automotive accessory manufacturing firm, began developing Stebro cars from his Montreal plant partly to promote his brand in the Canadian market. He had moved to Canada from Europe after World War II, established an automotive repair business in Hamilton, Ontario, and later relocated to Montreal where he opened the Stebro Garage. Alongside his exhaust system business, Broeker pursued single-seat formula car racing seriously.
The Stebro Mark I, built in 1960 at the Stebro garage on McGill Street in Montreal, used a front-engined formula junior layout powered by a BMC unit. The Mark II followed as a mid-engined evolution, also BMC-powered. The Mark III was a modified Sadler MKV sports racer with an extended wheelbase. The Mark IV, constructed over the winter of 1962-63, featured a space-frame chassis of thin-wall chrome-molybdenum tubing, aluminium bodywork, and a modified Ford Formula Junior engine mated to a Hewland gearbox. Its suspension used conventional upper and lower A-arms at the front and a reversed lower A-arm with upper top link at the rear, with Girling brakes sourced from a Lotus 21 Formula One car at all four corners.
Broeker had planned to enter two cars in the 1963 United States Grand Prix at Watkins Glen, with John Cannon and Ernie DeVos as drivers. Cannon tested the Mark IV and found it capable, but departed to race for John Mecom in the United States. Build delays then ruled out completing the second car. The intended Martin Ford Formula One engine, based on the Ford of England 1500cc five-bearing block, was never delivered in time — the supplier kept promising imminent delivery while continuing development work to resolve reliability problems.
Faced with this setback, Broeker built up a stock Ford 1500cc engine using performance components from his existing race motors and trailered the car to Watkins Glen. DeVos, assessing the car as seriously underpowered, withdrew — leaving Broeker himself as the driver. During practice the front oil seal on the hastily assembled engine failed, releasing oil onto the circuit. Despite this, Broeker qualified, running just three and a half seconds slower than Baghetti's ATS.
In the race, the gearbox jammed in fourth gear after approximately three laps. Broeker continued, circulating with the car unable to reach full speed, but refused to retire. When the chequered flag fell, the Stebro was classified seventh. It was the last finisher, having completed 88 of the 110 laps. The result was historically significant: Broeker became the first Canadian to start and finish a World Championship Grand Prix, and the Stebro the first Canadian-built Formula One car to do the same.
In 1964, Broeker took the car to Europe for the inaugural European Formula Two Championship season, fitting a 1100cc Martin Ford engine. The underpowered combination produced best results of eighth places at Hockenheim and Zeltweg. Back in Canada for 1965, Broeker updated the Mark IV with a larger radiator, modified bodywork, and a Lotus Ford twin-cam engine. In this form the car won many outings over the following three seasons across Formula Libre and Formula B class events in North America, accumulating over 100 victories.
In late September 1968, Broeker crashed the car heavily at St. Jovite. The car was rebuilt and tested but handling problems led Broeker to purchase a Chevron rather than rebuild the Stebro further. The original Mark IV was retained as a spare and eventually deteriorated after Broeker's death in 1980. A subsequent owner purchased it in 1985 and completed a full restoration, racing it in the vintage class at the Canadian Run-Offs at St. Jovite in September 1988, where it won its class.
Beyond racing, Stebro's identity was built on its performance exhaust systems business. Broeker had introduced the brand around 1959, initially importing products through an association with Frank Reisner before manufacturing locally in Pointe Claire, Quebec. The exhaust business continued after the racing programme ended and outlasted Broeker himself. The Stebro name was later revived by a Swiss mechanic, Andy Petschenig, who relaunched it near Ottawa, Ontario, focusing on Italian automobile applications with stainless steel products, though the revived company went out of business in 2013.