BMW’s N63 and S63 engines are unique in that the exhaust and intake arrangements are reversed when compared to a traditional V8 architecture. That is, the exhaust manifolds and turbochargers are positioned in valley between the cylinder heads. The big difference between the N63 and the S63 is that the S63 exhaust manifold is designed with a pulse-tuning effect for more performance.

By mounting the twin-scroll turbos on top of the engine, packaging is not only improved but turbo lag is reduced due to the shorter distance the spent gasses have to travel before hitting the turbine blades.

All that engineering is negated if you don’t have the exhaust manifolds and turbos bolted in place. Some BMW shop posted these videos of an open exhaust on an N63 engine. Below is without turbos, while the lead video is without the manifold.

No indication of the shop’s identity, but there is the obligatory “We’re experts, don’t do this at home” warning. Check out the videos for yourself and enjoy the fireworks!