BMW M240i v AMG A45 v Audi RS3 v Golf R Dyno Comparison

One of the things that makes Carwow videos interesting is how they compare cars in different ways. In this case, a power-to-weight comparison between a BMW M240i, AMG A45, Audi RS3, and Golf R. But the best part? It’s entertaining to watch. 

It starts with the Volkswagen Golf R. Powered by a 2.0-liter turbo four-cylinder with an advertised 320 horsepower, it’s equipped with a seven-speed automatic gearbox and all-wheel-drive. The owner thinks his car makes somewhere around 325 horsepower, which turns out to be almost on the nose. The highest of three dyno runs came in at 324.6 horsepower. 

Next up is the BMW M240i. As one of the more powerful versions of the BMW 2 Series, the M240i came equipped with a 3.0-liter turbo cranking out 347 horsepower. Like the Golf R, the owner of the BMW thinks 347 is a bit low, in this case, it should be closer to 400 horsepower. Again, the car makes more power than advertised, but at 375 horsepower, it’s shy of what the owner expected.

Moving on to the Audi RS3, we have a 400-horsepower 2.5-liter five-cylinder turbo. According to its owner, it should make somewhere around 410 to 415 horsepower. Like the Golf R, it has an all-wheel drive and a seven-speed gearbox. Also, like the owner of the Golf R, the owner of the RS3 is spot on with his estimate. The actual number came out to 413 horsepower. 

Finally, it’s the Mercedes-AMG A 45’s turn. Its 2.0-liter turbo four-cylinder puts out a factory-claimed 421 horsepower. Like all of the cars, it’s all-wheel drive with an automatic gearbox, in this case with eight speeds. But unlike the other owners, the person who owns this Mercedes thinks it produces slightly less power. His guess is somewhere around 417. It turns out he was right to be pessimistic because the car only makes 386 horsepower. 

So who won? In this competition, the challenge was not about sheer power but the power-to-weight ratio. Each car was also weighed and Carwow calculated the ratio using its recorded numbers against the English ton, which is 2,240 lbs. Using those calculations, the Audi RS3 came in first with 254 horsepower to the ton, followed by the Mercedes-AMG, BMW, and finally, the VW.