It’s quite amazing what some tuners can get out of the 3-liter straight six engine found under the hood of the BMW M4. While the S55 engine got a lukewarm reception when it was launched, it continues to deliver unbelievable performance. Getting a 3-liter engine to put out 750 HP without talking about a proper race car is impressive, no matter how you look at it. That said, the M4 in the footage below managed to drastically outrun a Mercedes-Benz SL 63 AMG.
At first, you might be tempted to play the numbers’ game and blame me of being biased but I should also point out that while the M4 might’ve been extensively tuned, the SL63 wasn’t running stock either. The 5.5-liter V8 under the hood of the GT car was pushed far from its stock numbers as well. Instead of 585 HP the AMG was now delivering, according to the Youtube video at least, around 750 HP, a similar figure as the BMW.
But while the Merc uses a 5.5-liter engine, the Bimmer makes due with almost half that. And yet, with 250 HP/liter, the Coupe is a proper land rocket. That becomes rather evident once the two set out in the video below. At the same time, there’s yet another factor at play here: weight.
While the M4 has four seats and is definitely the more practical car, the retracting hardtop of the Affalterbach machine adds some serious weight to its already generous hips. Therefore, the two are separate by some 200 kilos (400 lbs) and that would definitely have tipped the scale in favor of the M4. Then there’s the difference in skill behind the wheel that, in my humble opinion, made the biggest difference here, with the driver of the SL63 botching at least one gear shift and thus losing this showdown.