Egon Booms' Mercedes-Benz PontoonI have always loved Q-cars. The idea of putting a big, tricked-out engine into a small car, and seeing the look of surprise on the faces of sports car drivers as you leave them in the dust has its own brand of appeal. These days major manufacturers play this game very well indeed. BMW's M5 and the E63 AMG are just two examples of factory-built four-door hot rods that can really upset drivers of junior league supercars.
However, there's something even more enticing about dropping modern mechanicals into a classic car, giving it a turn of speed that would do justice to the racing cars from its era.
My old high-performance road and race driving coach, John Lyon, had a car like that back in the 1970s. It was a green Morris Minor Convertible powered by a tuned 110-hp Mini Cooper S engine. A lower Koni suspension, wider steel wheels and big brakes kept it from departing into the scenery, and were the only clues to its non-standard mechanicals. Of course Lyon was a master behind the wheel, and the number of big car drivers he upset with this innocuous looking but very rapid granny car was legendary.
Today I'm in the small village of Hinte, near the coast of Northern Germany, and I have come to see a 1950s classic Mercedes Ponton with the heartbeat of a 35-year-younger model.
The Ponton has a special place in my personal motoring experience because when I was 12 and living in Singapore, I was one of five youngsters taken to school every day in a grey 180D Ponton contract taxi. My lasting memories of this car was a clapped-out diesel engine that sounded like it was full of nails, and it felt like it could not pull the skin off the proverbial rice pudding. Forty-eight horses hauling a 2,600-pound car with six on board was no recipe for stirring performance.
Unlike some of the wild Frankenstein engine transplants companies like Brabus made in the 1980s, stuffing souped-up big-block S-Class engines into unsuspecting 190Es, this Ponton's creator, Dipl. Ing. Egon Booms, traded one four-cylinder Mercedes engine for another. However, his power unit of choice was not the tame 122-hp motor that powered the bog-standard 190E 2.0 liter. Instead, Booms went the whole hog with the 235-hp Cosworth-cylinder-head-endowed engine from the legendary 190E 2.5-16 Evo II.
Open the bonnet and you will see the cam cover bears the 2.3-16 script from the earlier 185-hp road car. "At the time I built it, this meant cheaper insurance," Booms explains, "but things have changed since, and it now no longer matters as the car is categorized as a classic and licensed for summer use in Germany." Interestingly, after inspecting it, the German transport office gave Booms manufacturer status; therefore his car has its own unique chassis number.
The high-revving 2,463cc motor is very over-square, with a bore and stroke of 97.3mm x 82.8mm. All DTM racers and their homologation road versions had to use fully working catalytic converters, and the 500 Evo II cars built for this purpose were no exception. So this late 1950s Mercedes meets mid-'90s emission standards.
Free-flow steel catalysts help the power, and a healthy 235 hp arrives at a screaming 7200 rpm, with the limiter at 7700 rpm. Torque output is 181 lb-ft between 5000 and 6000 rpm, and the 3.46:1 final drive helps the high revving engine at cruise.
When I first heard about this Ponton Cosworth, I wrongly assumed that Booms had simply performed an engine transplant and beefed up the chassis and brakes to cope with the near 300 percent increase in power. How wrong I was.
Wheeling out the photo album, he showed me the step-by-step build he performed in his spare time over seven years. He explained that his one-off special is actually the marriage of a Ponton bodyshell to the complete floorpan, axles, suspension, engine, brakes and interior of a 190E 2.5-16 Evo II.