Evolve LHD 4-1 Stepped Medusa Manifolds - BMW E39 M5FOR LEFT HAND DRIVE CARS ONLY The largest major restriction point of the E39 M5 S62 V8 engine is the exhaust manifolds headers. Changing the exhaust system without changing the headers gives no gain in power. In fact, changing the header back system gives little if any power gain! The factory items are very poorly designed and looking at them it is clear funds were saved in the department. No other M Power car has ever had headers as poorly designed