The 2022 Cadillac CT5-V Blackwing has debuted as the most track-focused, most powerful, and fastest Cadillac product to ever be announced. That is undoubtedly helped by the fact that this new sports sedan carries an updated variant of GM’s supercharged 6.2L LT4 V8 engine. In Blackwing spec, the motor pumps out a ridiculous 668 horsepower and 659 lb-ft of torque. Thanks to one Jason Fenske over at Engineering Explained, we know a bit more technical data about the CT5-V Blackwing’s engine, and how it stacks up to the ill-fated 4.2L Blackwing V8 engine.
Let’s start with the 6.2L LT4 V8 found in the CT5-V Blackwing. While not exactly a new lump of metal, this engine has been revised by the team at Cadillac to make it even more potent than we’ve become accustomed to. Rotocast A356T6 aluminum cylinder heads, a ready wet-sump oiling and vent system, a higher flow air-intake, titanium intake valves, and a revised exhaust system all join the party for the 2022 model.
Modern stuff no doubt, but it is all combined with some old-school pushrod goodness. The LT4 is a single cam engine with two overhead valves per cylinder, with direct injection and variable valve timing. Instead of complicated modern turbochargers, boost is provided by a 1.7L four-lobe Eaton roots-type blower. Despite rocking 103.25 x 92mm bore and stroke measurements, the engine revs relatively high for a pushrod, up to nearly 7,000 RPM.
The 4.2L Blackwing V8 by comparison is a modern technical marvel. Only 1,400 of these V8 engines were ever built by General Motors, all of which found service in the CT6-V. The smaller displacement engine is twin-scroll twin-turbocharged, with the snails sitting amid the valley in a “hot V” setup. Unlike the classic small block, this engine features a dual overhead cam configuration, with four valves per cylinder and VVT on both the intake and exhaust runners. It produces 550 horsepower and 640 lb-ft of torque, or 131 horsepower per liter. The LT4 by comparison produces a lesser 108 horsepower per liter. That said, the original 4.2L Blackwing V8 doesn’t rev quite as high as the 2022 Cadillac CT5-V Blackwing’s 6.2L LT4, partially due to its 86 x 90.2mm bore and stroke ratio.
Following a comparison of how the two engines route their exhaust gasses and the functions that come along with that, Fenske poses a hard question. More specifically, he tries to answer which of these two Cadillac V8 engines is truly the best. The supercharged V8 is more powerful, more responsive, and revs higher. The turbo motor by comparison is a bit more refined, but also brings significant efficiency gains over the LT4. Nonetheless, we don’t really have to worry about this comparison, as the Blackwing V8 is no longer for this world.
No matter which V8 or how it ended up in the the 2022 Cadillac CT5-V Blackwing, we’re just glad it has a real engine.