Nobody will ever accuse the BMW X5 M and Mercedes-AMG G63 of being underpowered. In stock form, the AMG G63 delivers 577 hp and 627 lb-ft from a 4.0-liter twin-turbo V8, while the X5 M is slightly more powerful with a 4.4-liter twin-turbo V8 pumping out 600 hp and 553 lb-ft of torque.

That's more power than most SUV owners can probably handle (let alone use) but this hasn't stopped German tuner G-Power from taking them to the next level with its new range of aftermarket upgrades. If you want more power, G-Power's GP-700 kit extracts 700 horsepower from the X5 M and AMG G63.

Torque also increases to 627 lb-ft for the X5 M and 700 lb-ft for the AMG G63. This is already more power than you get in supercars like the Lamborghini Huracan Evo, but G-Power lets you go further. Upgrading to the GP-750 tuning package boosts the output in both SUVs to 750 hp, while the X5 M's torque increases to 664 lb-and the AMG G63's torque is boosted up to 737 lb-ft.

As well as remapping the ECU, G-Power fits both SUVs with a set of sport downpipes. For the AMG G63, G-Power adjusts the central powertrain control module, resulting in mountain-moving levels of torque. If you're somehow still not satisfied, the range-topping GP-800 upgrade transforms the X5 M Competition and AMG G63 into 800-hp super SUVs. With the upgrade installed, torque increases to 700 lb-ft and 774 lb-ft in the X5 M and AMG G63 respectively. Move over, Lamborghini Urus.

To achieve this insane power boost, G-Power installs larger turbochargers, while the G63 is upgraded with a GP-Deeptone exhaust system with adjustable valves for a deeper, more visceral soundtrack. G-Power hasn't released any performance specifications, but it's safe to say these upgrades will make these super SUVs faster than stock. For reference, the X5 M Competition will accelerate from 0-60 mph in 3.7 seconds and max out at 177 mph with the M Driver's package. The G63, on the other hand, will do the same sprint in 4.5 seconds and hit a top speed of 149 mph with the AMG Driver's Package.

With such obscene levels of power under the hood, you might expect these custom SUVs to come with garish body kits, but G-Power has taken a more subtle approach. Aside from the sports exhaust system and custom 23-inch forged wheels, there are no obvious cosmetic changes. G-Power also offers an 800-hp upgrade for the BMW M8.