Updated: Dec 11, 2022
The biggest engine in the M52 series is a 2.8 litre inline-six. In 1995, the M52B28 engine was released to replace the E36 328i, E39 528i, and E38 728i engines. The M52-series engine replaced the M50-series engine.
Similar to M50 engines, this engine features an aluminium cylinder block with a Nikasil coating on the cylinder walls. For the North American market, the M52B28 uses cast iron engine blocks instead of aluminium ones, and only the BMW Z3 model has aluminium cylinder blocks.
This choice was chosen because to the high levels of sulphur in US gasoline, which corrodes Nikasil and causes fast wear.
The connecting rods have a length of 135 mm. Aluminium pistons have a compression height of 31.82 mm. These numbers allowed the "square engine" result to be produced (84.0 x 84.0 mm bore and stroke).
The M52 2.8L engine's aluminium 24-valve DOHC cylinder head has variable valve timing just for the intake (single VANOS). M50TUB25 and M52B28 cylinder heads are compatible.
The M52TU was launched in 1998. There are a few enhancements as compared to the M52B. The most significant modifications are dual VANOS (variable valve timing system for both camshafts), variable geometry intake manifold (DISA), and cast iron sleeves inside the block.
The engine also received new pistons, connecting rods, and an electronic throttle body. The M52TUB28's camshaft specs are as follows: Valve lift 9.0/9.0 mm, duration 244/228 degrees.
The M52B28/M52TUB28 engine was produced until 2000, when it was replaced by the M54B30 engine, the M54 family's newest member.
Manufacturer: Munich Plant
Production years: 1995-2000
Cylinder block material: Aluminium
Cylinder head material: Aluminium
Fuel type: Gasoline
Fuel system: Fuel injection
Number of cylinders: 6
Valves per cylinder: 4
Valvetrain layout: DOHC
Bore: 84.0 mm
Stroke: 84.0 mm
Displacement: 2793 cc
Type of internal combustion engine: Four-stroke, naturally aspirated
Compression Ratio: 10.2:1
Power: 193 hp at 5,300 rpm, 193 hp at 5,500 rpm (TU)
Torque: 210 lb-ft (280 Nm) at 3,950 rpm, 210 lb-ft (280 Nm)at 3,500 rpm (TU)
Firing order: 1-5-3-6-2-4
Engine oil weight: SAE 0W-30, 0W-40, 5W-30, 5W-40
Engine oil capacity: 6.5 litres
Oil change interval: 6,000 miles (10,000 km) or 12 months
Applications: BMW 328i E36, BMW 328i E46, BMW 528i E39, BMW 728i E38, BMW Z3, Land Rover Defender
Problems and Reliability
Overheating: Overheating is a problem with the M52B28 engine. If a cylinder head overheats, it will be destroyed.
Oil usage: The oil rings in the engine are unreliable, and when they're bad, they use a lot of oil.
Ignition: Clogged hydraulic tappets/lifters may be the source of ignition issues. The ECU will turn off the ignition for cylinders with partially closed valves.
The M52B28 has a more refined design. Its engine life is less than that of M50 engines. All M52 engines have certain faults in common.
Remapping is usually the go-to for most people when tuning, however there are a verity of paths you can go down in order to tune your M52B28.
Fast road camshafts, sports exhaust manifolds, panel air filters, drilled and smoothed air boxes, intake headers, and remaps/piggyback ECUs are all common stage 1 upgrades.
Induction kit, sports catalyst & performance exhaust, ported and polished head, fuel pump modifications, and high flow fuel injectors are all common stage 2 mods.
Twin charging conversions, engine balancing and blueprinting, internal engine enhancements (head flowing porting/bigger valves), competition cam, crank, and piston changes to adjust compression, and adding or upgrading forced induction (turbo/supercharger) are all common stage 3 mods.
On the M52B28, the form and flow parameters of the air intake manifolds may have a significant impact on fuel atomisation. Although some manufacturers supply fairly well flowing air intake manifolds, most need motorsport components.
Larger intake pipes, smoother pipework, and a cold air feed or ram air feed may help improve power.
Fast road cams are one of the most important mechanical upgrades, but they must be fitted by someone who understands what they're doing, and they're not always easy to come by.
Note that these modifications will not add power on their own in most circumstances, but they may aid boost power after other mods by eliminating the limitation.
Forced induction is the most effective way to increase air supply, enabling you to burn more fuel and produce more power. It is one of the most expensive enhancements, but it yields the greatest benefits.
Porting and flowing the head has the purpose of getting air into the engine while reducing flow constraints and turbulence.
Increasing the M52B28 valve size, adding some port matching, and head flowing will also enhance power, and as a bonus, you'll be able to receive a bigger boost from other tuning tweaks.
Mapping should assist you in realising the full potential of all the components you've installed on your M52B28.
In certain circumstances, since the factory ECU is locked, flashing is not an option, therefore an aftermarket ECU is the way to go; many of these will exceed original ECUs but be sure it has knock protection and that it is correctly installed.
It will normally offer you roughly 30% more power on turbocharged cars and around 15% more power on naturally aspirated engines, but the final outcome will depend on the items you've installed and the state of your engine.