Have you ever heard of a “hot inside V”? It’s not a sandwich. Our friend Jason Fenske from Engineering Explained is here for a quick lesson on this en vouge turbocharging setup for today’s engines.
A hot inside V turbocharger layout places the turbo or turbos inside the valley between the engine banks. Mercedes-AMG offers this on its twin-turbo V-8 engines, while BMW and Audi offer hot V setups on a number of their products as well.
The benefit to such a setup is that the exhaust gas has a shorter path to flow from the manifold. They’re basically sitting on top of the exhaust manifolds. This allows for a much more narrow package placed under the hood.
Besides the short path, the exhaust side of the turbochargers remains hotter than if the turbos were outside of the V. The engine suffers from far less lag as the short path for the exhaust gases and the heat mean energy is used more efficiently, which keeps the turbos on boost. The engine in question, Mercedes-AMG’s 4.0-liter twin-turbo V-8, also provides peak torque at a lower rpm, and it offers a delightfully wide peak torque zone.
The hot inside V is a smart setup that’s being used in a lot of the high-end sports and luxury cars. The packaging and heat retention aspects are more efficient, and an engine that is more efficient is one that is able to produce its power more easily.