It’s a battle of the BMWs when an M5 Competition takes on a tweaked version of its little brother, the M3 Competition.

You wouldn’t normally consider this to be much of a race. The M5 is a much larger car, but it’s also extremely powerful thanks to a 4.4-L twin-turbo V8 engine producing 617 hp and 553 lb-ft of torque. That puts the M5 Competition in the same power-to-weight range as something like the Dodge Challenger SRT Hellcat.

It also has similar performance numbers. Zero to sixty is done in 3.2 seconds on its way to a limited top speed of 155 mph, or 190 mph with the optional M Drivers Package installed. Weight, however, is the only thing keeping this car back at 4,090 lbs.

On the other side of the line is the little M3. The plucky little coupe normally has 444 hp from it’s 3.0-L twin-turbo, but this one has been tuned to make 540 hp. Carwow doesn’t tell us exactly what work was done to it to give the extra 100ish horses, but it does put the M3 at least in the same ballpark as the M5.

However, the M3 weighs 400 lbs less than the M5, which might prove crucial in the coming races.

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But not the drag race. Here, the M5’s greater weight meant more traction since both cars had disabled their traction control systems on a wet track. The M3 just couldn’t find purchase on the damp pavement to get a move on, and the M5 simply walked away.

In the rolling race, things were different. Here, the M5 struggled to keep up with the lighter M3 to the point where it seemed like it would never quite be able to catch up.

The brake test, however, was more of a blowout. Although the M5 has carbon ceramic brakes compared to the M3’s steel discs, the M3 just has less car to stop than the M5. Both can stop in a hurry, but one is clearly faster at braking than the other.

So should you buy an M3? Maybe not right this second. The replacement M3 is due out in 2020, and it’s safe to say it’ll be the best M3 ever made.

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