Drag races are a good test of quickness and acceleration. We usually see high-powered vehicles contending in a straight-line race, mostly powered by engines that have more than four cylinders. But that isn't always the case.

More than a year ago, we've witnessed one of the slowest drag race ever. It was between an original Suzuki Samurai, a.k.a. the Suzuki Jimny, and a classic Volkswagen Beetle – both unlikely contenders but it happened anyway.

Gallery: Mercedes-Benz Actros 2018

Then, by June of this year, we've seen a Hummer H1 faced a modern Suzuki Jimny in another drag race. It was painfully slow, as well, especially with the H1 which weighs more than three tons. We weren't really sure which between the two races was the slowest, but that is now a moot point with this latest straight-line race from Carwow.

Lo and behold, bear witness to the slowest (and heaviest) drag race ever between the Mercedes Actros and Scania R500. Both were gargantuan 6x2 tractor units that weigh quite a lot, needless to say, but it's important to note that the Mercedes is powered by a 10.7-litre engine that makes 480 bhp, while the Scania has a bigger 13.0-litre mill that produces 500 bhp.

Moreover, since these tractors were made to haul massive loads, there was also a race with both of them pulling similar trailers. The trailers increase both of the trucks' weight to 44 tons or 39,916 kilograms apiece.

With these numbers laid out, which do you think was quicker to finish a quarter-mile? More importantly, which one braked better in the event of an emergency stop? Watch the video atop this page to find out.