The older M5 weighed 4,345 lbs (1,971 kg), whereas its successor weighs a massive 5,390 lbs (2,445 kg). It sticks to the twin-turbo V8 motor recipe, with the 4.4L unit pumping out 576 hp (585 ps/430 kW) and 553 pound-feet (750 Nm) of torque.
The electric motor brings 194 horsepower (197 ps/145 kW) and 206 pound-feet (280 Nm) of torque to the party.
BMW M states that the car's total thrust is 738 pound-foot (1,000 Nm), and the output is rated at 717 hp (727 ps/535 kW).
Naught to sixty-two mph (100 kph) takes 3.4 seconds, which is not bad at all from a business sedan that has a curb weight of nearly 2.5 tons. However, the old M5 used to deal with the sprint in 3.1 seconds.
The top speed remains the same at 155 mph (250 kph) or 190 mph (206 kph) with the available M Driver's Pack. The ultra-hot M5 CS was significantly faster, as it dealt with the sprint in a mere 2.9 seconds, or identical to the Ferrari 812 Superfast.
BMW's discontinued M5 CS enjoyed 553 pound-feet (750 Nm) of torque and 626 horsepower (635 ps/467 kW). However, plenty of tuners have your back if you plan on making it even punchier.
G-Power, for instance, can unlock no fewer than 808 horsepower (820 ps/603 kW) and 738 pound-foot (1,000 Nm) of torque. Unfortunately, this tuner did not reveal how fast its top proposal is, though we suspect the acceleration now takes 2.8 or perhaps 2.7 seconds.
A quick look on G-Power's website reveals that the upgrades will cost you a little over €25,000 in Germany, which comes out to almost $28,000 at today's exchange rates.
If that is a bit too much power for your taste, fret not, as the same tuner also offers lesser upgrades for the magnificent BMW M5 CS. For a little over €18,000 (~$20,100), you can get it with 769 horsepower (780 ps/573 kW) and 701 pound-feet (950 Nm) of torque.
Is that still a bit too extreme? How about a 740 ps tune for almost €12,300 (~$13,700)? This version enjoys 730 horsepower (740 ps/544 kW) and 664 pound-feet (900 Nm) of torque, and it is not the base offering.
The most humble oily upgrade for the BMW M5 CS from G-Power brings 690 horsepower (700 ps/515 kW) and 627 pound-foot (850 Nm) of torque to the party and costs nearly €5,000 (~$5,500), which is certainly not bad at all if you ask us.
But what else does the quoted tuner offer for the mighty BMW M5 CS besides the healthy power boosts mentioned above? Well, quite a few other things, actually.
The list includes the new hood with its more aggressive design, which will set you back a cool €6,545 ($7,305). This carbon fiber component joins a rear wing made of the same lightweight material, which costs €3,332 ($3,719).
A sports steering wheel will set you back €3,570 ($3,985). A new exhaust system and a V-max increase are also on the list, and the latter comes at €495 ($553).
G-Power's tuning bundle for the BMW M5 CS may not be the most exciting out there, but it is something worth considering if you own such a model and plan to make it even punchier.
Sure, the healthy power boost available in the top specification on the tuner's shelves may not be for everyone, but then again, the car itself is not for the average Joe, as it can give real supercars an ultra-fast run for their money, especially if we are talking about a straight-line sprint.
Mind you, the M5 CS is also a peach on twisty roads despite measuring nearly five meters (~196 inches) from bumper to bumper and almost three meters (~118 inches) between the axles.
For what it's worth, the BMW M5 CS remains one of the hottest versions of the model so far, and by the looks of it, it will be a good while until the German car manufacturer manages to come up with a faster executive sedan.
Chances are a CS version of the new-gen M5 is being considered, though it will have to be extremely powerful to beat the old one into submission.
Between us, we don't think BMW will launch a new M5 CS, as turning it into a supercar bully is extremely tricky and money-consuming.
Thus, if we were shopping for a used M5 and had the right budget, we'd certainly land a nice M5 CS, even if it costs as much as the 2025 M5. But would you also say no to the new M5?
