The LT4 V8 engine, to put it lightly, is a beast. At 650 horsepower and 650 lb-ft of torque, it’s easy to figure out why GM President Mark Reuss nicknamed the C7 Corvette Z06 “The Big Nasty.” However, it had an achilles heal, particularly in the C7; heat soak arrives fast and heavy – bad enough to where owners filed a class action lawsuit. And that’s largely why the C7 Corvette ZR1 has massive chipmunk cheek intake vents and larger extractor on the hood, to avoid the same issues with its 755 hp LT5. It’s also why companies like Callaway have come out with cooling upgrades to keep the temps of the C7 Z06 more optimal.
Similar issues weren’t reported with the sixth-generation Chevrolet Camaro ZL1, or third-generation Cadillac CTS-V, which also feature the LT4 V8 engine. The supercharged V8 was also deemed worthy to be placed in the finale of Cadillac’s ICE performance vehicle run: the 668 hp 2022 CT5-V Blackwing. Despite the potency, the negative reputation seems to linger, at least in the minds of GM performance enthusiasts.
So, do Cadillac CT5-V Blackwing customers have to be worried on a day at the race track? The short answer, “no.”
The LT4 Cooling Upgrades Of The Cadillac CT5-V Blackwing
Cadillac performance variant engineering manager Mirza Grebovic detailed to The Drive on how overheating issues are avoided with the LT4 V8 engine in the CT5-V Blackwing. He mentions the benefits of starting with a larger, more open surface area of the fascia of a sedan bodystyle. On top of that, Cadillac fit in two extra radiators to compliment the main unit, behind each headlight.
By using a sealed-off method, all the air that comes through the grilles is forced/tunneled through the cooling fins of the radiator instead of finding its way around the radiator and becoming useless. The grilles and the front bumper beam are also aerodynamically designed to make sure the air flows where it is supposed to. Although these pieces are in front of the radiator, they are engineered to direct flow to all parts of the radiator cooling fins.
Along with some of the mystery in the front bumper, there are also front brake cooling ducts that you wouldn’t even know were there if you didn’t know what you were looking for. And on the front fender behind the front wheels are fully functional extraction vents that let out hot built-up pressure in the engine bay helping keep fresh cool air coming in and hot air going out.
If you were still wondering if enough has been done to prevent the LT4 from overheating in the Cadillac CT5-V Blackwing, engineers say they have had it out in 90-plus degree heat all day on the track with no problems. They included tests like lead-follow laps, hot laps, open-track sessions, and plenty of braking and idling tests under all kinds of conditions.