Cadillac CT5-V Blackwing vs. AMG E63 S, BMW M5, Audi RS7

The Cadillac CT5-V Blackwing is finally here, and the spiritual successor to the CTS-V we loved so much is an even heavier shot across the Atlantic than we expected. Its 6.2-liter supercharged V-8 kicks out a (frankly ridiculous) 668 horsepower and 659 lb-ft of torque. That’s not just “a lot,” it’s enough to put the the European super-sedan aristocracy—the BMW M5 CS, Mercedes-AMG E63 S, and Audi RS7—to shame.

Before we get started, it’s worth noting that both the CT5 and its smaller sibling, the CT4, are what we generally refer to as “tweeners,” meaning their specs land them between established segments. Say, their overall length and wheelbase places them in one segment, but their pricing puts them in another. The non-V CT5’s base price, for example, is $37,990, while the BMW 5 Series starts at $55,195—and even the smaller 3 Series runs $42,245 to start. This, despite the fact that the wheelbase measurements of the CT5 and the 5 Series are within 1.1 inches of each other (116 inches to 117.1). So, the CT5 is not-quite-a-5er, not-quite-a-3er, making the CT5-V Blackwing closest to, well, the more powerful uber-fast midsizers than less powerful, smaller stuff such as the BMW M3 sedan or Mercedes-AMG C63. How does the Caddy do against the M5, E63 S, and RS7, then?

Let’s talk weight. While we haven’t tested the new RS7, we did recently weigh its wagon sibling, the RS6 Avant. The RS6 weighs in at a hefty 4,862 pounds, and it’s safe to assume the RS7 shaves a few pounds off that curb weight. Mercedes-AMG claims the E63 S sedan tips the scales at just under 4,500 pounds; we also recently put the E63’s wagon counterpart on the scales, and it weighed in at 4,568 pounds. The last M5 we tested was a non-Competition-spec M5 from 2018 and it weighed in at 4,268 pounds. The new, more powerful M5 CS promises to be lighter than the already slimmed-down M5 Competition, and will probably come it at around 3,900 pounds all in.

The Cadillac’s weight, on the other hand, is a bit more elusive. At Car of the Year evaluation last year, we tested a regular CT5 with the 2.7-liter four-cylinder engine that tipped the scales at a relatively svelte 3,693 pounds. The Blackwing, on the other hand, has a more than twice-as-big engine, but lacks the all-wheel drive included on the M5, E63, and RS7. The Blackwing also comes with the option for carbon ceramic brakes and can be had with Magnesium wheels, both of which reduce mass. Not to mention the Caddy’s liberal carbon fiber trim. That means that, even if the CT5 gained 200 pounds in the transformation to Blackwing spec, it would still weigh much, much less than all of its German competitors.

As for what’s under their respective hoods, the story is much the same from Audi, BMW, and Mercedes. All of those sedans come with twin-turbo V-8s. The Mercedes and Audi both displace 4.0 liters, the BMW displaces 4.4. Now, just for a moment, consider that we live in a world where the RS7, with its 591 horsepower and 590 lb-ft of torque, is the least powerful member of this quartet. That’s just nuts.

Anyway, the Mercedes makes a mighty 603 hp and 627 lb-ft of torque, while the recently-announced M5 CS makes 627 horsepower and 627 hp and 553 lb-ft. Those figures merely contextualize what you already knew: The lighter, more powerful CT5 Blackwing is going to have a vastly superior weight-to-power ration when compared to the M5, E63 S, and RS7.

Thing is, the CT5-V BW might not be capable launching as hard as its all-wheel-drive competitors, given its rear-wheel drive, but that’s a decision Cadillac claims was intentional. The automaker left AWD off the table because, on a racetrack, the extra driven wheels apparently don’t make the car any faster. In brief, the acceleration times of the rear-drive-only CT5-V Blackwing and its competitors may be more clustered than you’d expect, given the Cadillac’s power-to-weight advantage.

Other trick, go-faster bits are common to every entry in this foursome. All of them come with the option for ceramic brakes, lightweight wheels (though it must be mentioned only the Caddy’s are exotic magnesium), and adjustable dampers. However, only the Cadillac offers the option of a six-speed manual transmission; the BMW, Mercedes-AMG, and Audi are all automatic-only. A 10-speed auto is available, but the stick alone might be a good reason to go for the Blackwing.

Another good reason to consider the Cadillac? Dollars and cents. Remember what we said about the CT5 being a tweener? That gives it a massive price advantage, even when you massively scale-up the performance. The E63 S starts at $108,495, the RS7 at $114,995, and the M5 CS breaks the bank at $142,995. The Caddy, on the other hand, starts at $84,990. So, just to get it all straight, the CT5 Blackwing makes (way) more power, weighs less, offers a manual gearbox, and costs more than $20,000 less than its closest rival. This thing might be the bargain of the century—but we’ll need to put it head-to-head with its competitors and drive them all at once to see which one truly comes out on top.