Update: Mercedes AMG has released more M178 photos from the dyno room and assembly plant. There are also closeups of a cutaway engine showing more detail of the intake and exhaust manifolds. See the additional photo gallery below.

Details and photos of a new 4.0-liter twin-turbo V8 that will offered in the upcoming Mercedes AMG GT supercar have been released.

Boasting 503 horsepower at 6,250 rpm and code-named M178, the engine follows the current trend of boosted downsizing to produce power while improving fuel economy and reducing emissions.

According to Mercedes, at least 650 Nm (480 lb-ft) of torque will be available from 1,750 up to 4,750 rpm. Redline is 7,200 rpm.

Like many of the new clean-sheet boosted engines of today, the Borg-Warner turbos are positioned between the cylinder banks to reduce plumbing nightmares and get the exhaust heat closer to the turbine for reduced turbo lag. The arrangement also helps with overall packaging for the intercoolers under the hood and reduces weight. Boost is expected to peak around 17 pounds, obviously leaving room for more performance.

In keeping with the GT’s road-hugging persona, dry-sump oiling will be used to help lower the vehicle’s center-of-gravity (no worries over oil-pan clearance) and maintain lubrication under high G-load cornering. Total engine weight is listed at 461 pounds.

The 90-degree block is designed around 90mm bore centers and sports 83mm bore diameters. Crankshaft stroke is 90mm, resulting in total displacement of 3,982cc. Innovations include Nanoslide coatings on the cylinder walls and unique piston-ring packages to reduce friction. The engine also features variable valve timing and Piezo injectors.