BMW S54B32 engine

With the beginning of production in 2000 by the Bavarian automobile concern BMW M3 model on the E46 body is installed a new engine S54B32, which replaced the M.

S-series motors for BMW S54B32 with existing specifications are sporty variants for civilian cars, efficient atmospheric engines with a displacement of 3246cm³, capable of developing up to 343hp/365nm at 4900rpm. Thanks to the installed Siemens MSS54 engine control unit, minimizes errors.

Retaining the cast iron 6-cylinder block of the predecessor, but with an increased diameter of 87mm and piston stroke of 91mm, with a compression ratio of 11.5, compression height of 32.3mm – a distinctive feature from previous models. Reinforced forged connecting rods 139mm long and forged crankshaft, with 12 counterweights, held on 7 bearings, the use of cooling of enlarged pistons (made of cast aluminum with subsequent graphite coating, weighing 470g) with oil nozzles – increased the reliability of the car unit.

In order to achieve positive efficiency of the S54B32 engine, electromechanical Double VANOS (or double VANOS) timing control equipment is installed, which regulates the functioning of the intake and exhaust valves. This ensures smooth engine operation at different engine speeds, reduced fuel consumption, reduced exhaust emissions, and increased power with increasing crankshaft speed.

The use of cast iron hollow camshafts in the BMW S54B32 was an excuse to reduce the weight of the cylinder head.

S54B32 engine specifications

Disadvantages

The resource of the engine in question is quite impressive, reaching the limit of 200,000 km of mileage. But this figure is reduced by regular extreme driving.

Engine S54B32, its technical characteristics, confirmed by a solid period of active operation, does not have such a flaw as excessive oil consumption. But if this happened – a sure sign of the need to replace valve seals or piston rings. The absence of hydraulic valve tappets forces the car owner to adjust them every 50 thousand kilometers with the help of special washers.

As practice shows, after 150 thousand kilometers of mileage – liners, timing chain, tensioners need to be replaced.

• Increase in coolant temperature, overheating of the M3 E46 engine occurs only after the appearance of an air lock in the cooling system, pump or thermostat malfunction. Contamination of the radiator, improper functioning of the radiator cap are not uncommon causes of engine overheating.
• Overheating, mechanical damage, voltage drop leads to failure of the electronic engine control unit, which results in the cessation of normal operation of the unit.
• The VANOS system ensures economical and environmentally friendly engine operation. But failure of oil piston sealing rings, wear of washers and bearings, driving on contaminated oil and gasoline are the main reasons for failure of stable operation of the GDS.
• Regular oil changes, use only original oil, use clean gasoline, and perform maintenance within the factory recommended timeframes are the key to long-term trouble-free operation of the engine.

Modifications

• The model variant of the 343-horsepower modification of the unit S54B32EU – was installed on BMW models for operation on the European continent.
• S54B32US is a less powerful (333 hp) representative of the range for vehicles used in the USA. Due to special requirements for CO2 emissions, changes were made to the location (closer to the engine) of the dual catalytic converter, which affected the overall power parameters. Some cars had a claimed power of 325 hp (Z3 M Coupe, Z3 M Roadster).
• The lightweight version of the base model – S54B32NR – was used only for the BMW M3 CSL E46. Lightweight intake and exhaust manifolds, modification of camshafts, air intake through a hole in the bumper, flow through the installed carbon fibers in the air intake, use of a special engine control unit MSS 54HP – are the distinguishing features of this model from the base model.

S54B32 engine tuning

The factory performance of the S54B32 is quite good. Some amateurs are willing and able to improve them.

S54B32 turbo

Additional installation of a branded compressor kit from ESS increases engine power, from the baseline, up to 600hp. The procedure for performing is not so complicated, but it is a costly item. Automechanics recommend initially purchasing models with turbocharging, than to buy and mount independently.

Camshafts

This modernization needs to be done in a comprehensive way. Replacing the intake system, full sport exhaust and control unit will help increase power (just over 370hp) without dismantling the combustion engine.
To increase the actual power even further, a complete camshaft replacement is required, with the springs and plates replaced at the same time. This will increase the power to 400hp at 8500rpm.

Selection of pistons and replacement for a higher compression ratio (≥12.5), with simultaneous disconnection of the VANOS engine control unit, increasing the engine speed is possible, but not rational. And the probability of engine destruction is high. The cost of components is not cheap, it is costly in terms of time period. It is much cheaper and, most importantly, without problems – to buy another car.

This engine is installed on the following models:

BMW M3 (E46)

BMW Z4 (E85)