The GMC Yukon AT4 was built with off-road-ready capability right from the factory, but if it’s power that you really want, then the speed freaks at Hennessey Performance Engineering have a solution. As it turns, out, Hennessey is now offering its H650 package, which, as you might guess, ups the ante to 650 horsepower – quite the sum for the GMC Yukon AT4. Now, we’re watching all those ponies stretch their legs in the following video.
The video is a bit over four-and-a-half minutes long, and includes all the usual high-speed shenanigans at Hennessey’s test track in Texas, plus some driving impressions and a little insight into the H650 package.
The star of the show is the new 3.0L supercharger, which bolts on top of the GMC Yukon AT4’s 6.2L V8 L87 gasoline engine and looks good in the process. The supercharger is complemented by a laundry list of performance upgrades and add-ons, such as a high-flow intercooler and air induction system, chromoly hardened pushrods, a new crankcase ventilation system, a stainless-steel cat-back exhaust, and of course, Hennessey’s engine management calibration. Customers also have the option to add in a performance wheel and brake upgrade, with stoppers from Brembo to help shed some of that speed when needed.
Put it all together, and the H650 package throws down with 650 horsepower at 5,500 rpm and 658 pound-feet of torque at 4,200 rpm. That’s a lot, especially compared to the 420 horsepower at 5,600 rpm and 460 pound-feet of torque at 4,100 rpm produced by the GMC Yukon AT4’s 6.2L V8 L87 in stock guise. Add in a 3-year / 36,000-mile limited warranty, and it definitely makes for a tempting upgrade.
While the power bump is definitely nice, the extra torque should make the biggest difference in terms of daily driving, as pointed out by the Hennessey team in the video.
Check out the full feature video below: