BMW N53

BMW N53 engine
Overview
Manufacturer	BMW, Bayerische Motoren Werke AG
Production	2007–2014
Combustion chamber
Configuration	Straight 6
Chronology
Predecessor	BMW N52
Successor	BMW N20, BMW N55

The BMW N53 is a straight 6 DOHC piston engine which was produced from 2006 to 2011. It is the final naturally aspirated straight-6 engine produced by BMW, ending a history of continuous production of this engine configuration since 1968. The N53 released in 2006 in the facelifted E60/E61 523i and 525i. Following the introduction of the N20 turbocharged straight-4 engine in 2011, the N53 began to be phased out. The N54 turbocharged straight-6 engine was produced alongside the N53, therefore the N54 took over as the highest performance six-cylinder engine.

Compared with its N52 predecessor which was port-injected, the N53 uses direct injection (consisting of Piëzo-electric injectors directly in the cylinder) with a stratified lean mixture operation. The N53 has variable valve timing on both camshafts (called double vanos by BMW) and a magnesium alloy block. Unlike the N52, the N53 does not contain variable valve lift (called valvetronic by BMW), due to space limitations in the cylinder head.

BMW never sold the N53 engine in North American, Australian and Malaysian vehicles, due to the high sulphur content of the fuel available in these markets. These regions continued to use the N52 port-injected naturally-aspirated and N54 direct-injection twin-turbo inline-6 engines for the 2007-2011 model years.

The 2.5-litre N53B25-U0 is used in the E60/E61 523i and produces 140 kW and 235 Nm.

Applications:

The E90/E91/E92 325i switched from the 2.5 litre N52 to the 3.0 litre N53B30-U0 in March 2007. Despite the increased displacement, the maximum power remained unchanged at 160 kW.

...
Wikipedia