The BMW 730Li was technically practically identical to the BMW 730i apart from a 14 cm longer body. The engine used here was the M54 engine that was already in service in the BMW 5 Series, BMW 3 Series and BMW X5. Both the crankcase and the cylinder head were made of an aluminium alloy in order to save weight. The fully variable control of the opening timing for the intake and exhaust valves helped to save fuel.