Manoli Katakis 
The 2021 Chevrolet Tahoe has been trickling into dealerships nationwide right now. By all accounts, the all-new SUV is a revolutionary product, and brings new levels of sophistication to the nameplate. Namely, an independent rear suspension that not only improves ride and handling, but also helps expand interior cargo volume some 30 percent, while barely growing in overall exterior dimensions.
That said, a tried-and-true powertrain combination can still be found under the hood: a standard 5.3L L84 V8 engine pushing out 355 horsepower, and an optional 6.2L L87 V8 pushing out 420 horsepower. Both engines feature dynamic fuel management, which is a technology that allows the engine to operate on a variable cylinder combustion operation, from all eight, down to just one. The 3.0L LM2 diesel engine will also be available on the 2021 Chevrolet Tahoe.
Just as the new SUV is hitting dealerships, its also being ordered by tuning shops. In this case, Hennessey Performance Engineering. They appeared to have gotten their hands on a 2021 Tahoe with the optional 6.2L V8, and wasted no time on strapping it to the dynomometer. The results? 369 horsepower and 397 lb-ft of torque at the rear wheels. The video is just below.
Considering their mechanical sameness, this dyno test result for the 2021 Chevrolet Tahoe with the 6.2L L87 V8 can also be applied to the 2021 GMC Yukon and 2021 Cadillac Escalade with the same engine. As can its locked ECU. That’s right, the cybersecurity of GM’s Global B electrical architecture is present and accounted for in all T1 platform SUV products. And we told everybody who would listen a while ago. But unlike the clickbait C8 Corvette videos, Hennessey appears to be coming clean. In their video caption, they state the following:
“We hope that GM will consider working with SEMA and the aftermarket industry to come up with a tuning solution for these vehicles. But for now and the foreseeable future, stock power is about all you’re going to get out of their new vehicles. If you want to modify your new SUV you’ll need to buy something else.”
Okay so let’s see a blown 6.2. I will never get a 5.3. No replacement for CI’s add a blower or twin turbos, probably a good chip and I am good to go as long as it Isn’t black.
You can’t tune/chip/supercharge these new engines.
I had a 2018 z-71 5.3 bought a 21 Trai boss 6.2. The only thing I can say is Beast mode in a truck.