The BMW 5 Series E34 is the third generation of the Bavarian premium business sedan. The premiere of the new model took place in 1987, and sales started in 1988. In 1991, the all-wheel drive version of the BMW 525ix entered the market.

E34 has been updated twice. First time in 1992 - the modified version can be identified by other mirrors. The new ones have become much more harmonious and acquired more aerodynamic forms. The M50 engine received a VANOS variable valve timing system, and a 5-speed one took the place of a 4-speed automatic. The driver's airbag no longer required a surcharge and was included in the list of basic equipment, like ABS.

Two years later, the BMW 5 Series E34 underwent another restyling. This time, the front grille has been changed, which is wider. From now on, the German sedan has become mandatory to be equipped with two airbags - the driver and the front passenger. In 1996, the E34 gave way to the next generation BMW 5 series E39. In total, 1,330,000 copies of the third generation "five" were sold. This is almost twice as much as its predecessor - E28.

Engines

Gasoline:

R4 1.8 8V (113-115 HP), 518i;

R6 2.0 12V (129 HP), 520i;

R6-VANOS 2.0 24V (150 HP), 520i;

R6 2.5 12V (170 HP), 525i;

R6-VANOS 2.5 24V (192 HP), 525i, 525ix;

R6 3.0 12V (184 hp), 530i;

V8 3.0 32V (217 hp), 530i;

R6 3.4 12V (211 hp), 535i;

V8 4.0 32V (285 hp), 540i;

R6 3.5 24V (315 HP), M5;

R6 3.8 24V (340 HP) M5.

Diesel:

R6 2.4 12V (115 HP) 524td;

R6 2.5 12V (115 HP) 525td;

R6 2.5 12V (143 HP) 525tds.

Looking at such a wide range of engines, a dilemma arises - which motor to choose, more powerful or more economical. But before making a decision, there are a few things to be clear.

If you are looking for a relatively economical gasoline engine, then you should pay attention to the 2-liter engine with variable valve timing VANOS. However, it must be borne in mind that sometimes this system fails. The dynamics with such a motor is not impressive - 10.6 seconds to 100 km / h. But low fuel consumption and rare breakdowns are guaranteed.

An 8-valve 1.8 liter is better not even to consider - it is too weak. Much preferable is the 120-horsepower BMW 520i with М20В20, which the Bavarian inherited from the previous generation E28 model. Its disadvantages: wear on the camshaft, rocker arms, valve seats, and sometimes the valves themselves.

The best compromise between fuel consumption and dynamics is provided by the in-line 6-cylinder 2.5-liter petrol engine, especially its 24-valve version (M50). Fuel consumption in the city is about 15 l / 100 km, and outside it - up to 10 l / 100 km.

Attention! All 12-valve versions of gasoline engines easily overheat, which leads to breakdown of the gasket under the head, and sometimes to damage to the head itself. To rule out the possibility of an incident, it is necessary to constantly monitor the state of the thermostat, and much more often than in any other car, look into the coolant tank. But above all, you need to pay close attention to the engine temperature gauge.

A typical disease of 6-cylinder gasoline engines is the failure of the water pump. Depending on the series, a plastic impeller was installed in them, which, as a result of exposure to high temperatures, became brittle and separated from the shaft. This led to overheating of the engine and deformation of the block head. It is comforting that metal impeller pumps are currently available.

The viscous coupling of the fan also requires attention. Its malfunction can lead to overheating of the engine and, as a result, to damage to the block head.

The powerful V8 engines, installed since 1992, and the top model M5 guarantee not only sporty dynamics, but also huge fuel, maintenance and repair costs. The most typical malfunctions: drop in compression, burnout of the collector gaskets and uneven operation.

The rest of the gasoline engines, although they consume an impressive amount of fuel, as a rule, do not create much hassle during operation. However, it must be borne in mind that the BMW 5 E34 is no longer young, and therefore malfunctions associated with high mileage are quite natural.

Diesel modifications are best avoided. Almost all of them force to solve problems caused by overheating of the block head and its subsequent cracking. In addition, the injection system is capricious and the turbocharger is not too hardy. Today, it is more and more difficult to find a service that can handle the repair of a Bavarian injection pump. In addition, diesel versions already have astronomical mileage. An attempt to find an unbroken copy borders on a miracle!

Engines of the M20 series (520i and 525i), as well as motors of versions 518i and 524td, are equipped with a timing belt, which must be changed every 60,000 km. The rest of the units are equipped with an almost eternal timing chain.

Design features

E34 traditionally for BMW has rear axle drive. The model range also included an all-wheel drive modification of the BMW 525ix. The engines were combined with one of four gearboxes: 5 and 6-speed mechanics or 4 and 5-speed automatic. The chassis is based on MacPherson strut front and multi-link rear.

Typical malfunctions

First of all, you need to pay attention to the suspension components. Worn stabilizer struts and bushings, levers, silent blocks, ball joints and shock absorbers should not surprise anyone, because the car is already at a respectable age. If you do not save on substitutes, then after the repair you will not think about the suspension for a long time, because it has a rather strong structure. However, bad roads can quickly finish off the ball, bushings on the front levers and rear beam.

For age reasons, there are often problems with the steering. After 150-200 thousand km, a backlash appears in the steering gear, and then leaks. The parking brake requires regular maintenance.

One of the common ailments of the BMW 5 Series E34 is corrosion. It appears on the lower edge of doors, fenders, sills, boot lid and fuel filler flap. Rust is often found on brake lines as well.

Electronics also does not stand the test of time: comfort module, central locking, power windows and heating.

An automatic transmission, if the oil and filter are changed in time, will work for a long time. But remember that the lack of only a glass of oil (0.2 l) leads to improper operation of the automatic transmission and to the rapid wear of its components. Nevertheless, often after 150-200 thousand km, malfunctions occur due to damage to the torque converter or planetary mechanism.

In the transmission, it is worth paying attention to the propeller shaft support and its joints, the rear differential and the axle joints. Problems with the above components are often found in cars from under the owner, who prefers to press the gas pedal harder and all the way to the stop.

Conclusion

Despite these shortcomings, the BMW 5 E34 is considered one of the most durable German cars of the late 80s and early 90s. Some would argue that the reliability of the Bavarian sedan can be compared to the Mercedes-Benz W124. Unfortunately, at one time, many cars fell into the hands of careless young drivers who did not feel too sorry for BMW and did not take good care of it. Today it is almost impossible to find an E34 in good condition. But if you succeed, you will be rewarded with excellent handling and dynamics, very rich equipment, decent comfort and timeless design. True, in addition to the above-mentioned malfunctions, the inconvenience can be delivered by the prices of some of the spare parts that are by no means cheap.

Perhaps one of the most legendary "five" in the history of the Bavarian concern. This car was first presented in '88. "Thirty-four" made a splash among journalists. Many predicted a great success for this body. And so it happened. The car attracts attention to this day. One of the most popular modifications is the 525. What is the BMW 525 E34? Photos, specifications and much more, see further in our article.

Design

The car has a signature shark look with round twin headlights. This series was the first to use xenon optics. It was available in all BMW E34 525 models, regardless of the configuration.

The massive arches accommodate wheels from 15 to 18 inches in diameter. Also, the car has a strong bumper. As the reviews say, the BMW 525 E34 is a real tank in terms of body resistance to impacts. But over time, the metal starts to rust. In particular, this applies to models with a hatch. Over the years of operation, drainage holes are clogged. As a result, fenders, sills and underbody suffer. The car has excellent aerodynamics. By the way, the hood opens in a sporty way, away from the windshield. The design of the car is so well composed that even now the "five" does not look like a dinosaur from the past. In this form, the car was produced until 94.

Then she underwent restyling. The changes are minimal, but they are there. So, the radiator grille and the lugs on the hood became wider. The back has remained the same. But the main changes did not affect the design or even the interior - the Germans improved the technical "stuffing" of the sedan. But we will talk about it a little later.

Salon

Inside, the car has a similar design to that of the "seven" premium. But the panel is a bit narrower here. Nevertheless, even the most well-fed driver will be able to comfortably sit behind the wheel of this "barge". The machine has well-thought-out ergonomics and high-quality sound insulation.

A distinctive feature of the German sedan is the floor-mounted accelerator pedal. It is very convenient to dose gas with it, the reviews say. As for the upholstery, it depended on the configuration. So, in the initial versions, the BMW 525 interior in the E34 body was fabric or velor. More expensive trim levels featured a dark leather interior. In rare cases, the skin was light - this is the lot of the "seven" from the premium segment. The car has a cleverly implemented center console. So, it is slightly turned towards the driver and is "equipped" with all kinds of systems. One of these is the pixel on-board computer. Next to him was a radio tape recorder and a climate control unit. The trunk volume of the sedan is 460 liters. The backrest does not fold down. A complete toolbox was provided in the trunk lid.

The instrument panel is convenient and informative, with readable white scales. There was also a small display with an on-board computer under the speedometer. It showed data on daily and total mileage. But the current consumption was shown by an arrow located under the tachometer scale.

During the restyling, the interior design of the BMW E34 525 did not change at all (there was only a second airbag for the front passenger, integrated into the panel). But the owners had no complaints about this. Reviews say that even many modern cars do not have such a comfortable interior - the "five" has surpassed its time so much. Well, let's move on to the technical part.

BMW 525 E34: specifications

Since we are considering modification 525, we will focus only on the 2.5-liter engines. There were several of them in the lineup. So, initially a gasoline inline 6-cylinder M20V25 engine was installed on the sedan. Its maximum power was 170 horsepower and torque was 222 Nm. But even with this engine, the car showed excellent dynamic characteristics. BMW 525 E34 accelerated to a hundred in 9 and a half seconds, and the maximum speed was limited to 220 kilometers per hour.

As for fuel consumption, it is quite moderate. For a hundred in the city, the car spends 11.4 liters of fuel, on the highway - 6.8. М20В25 - the simplest motor in its design, which was installed on the "thirty-four". The old timing system without vanos is implemented here, where there are 2 valves per cylinder. The block of the motor is cast iron, and the compression ratio is 9 kgf. The resource of the motor, judging by the reviews, is about 300 thousand kilometers. Through a simple tuning (removal of the catalyst), the owners achieved an increase in power by 11 horsepower.

M50V25

This is a new generation of engines with an increased compression ratio of up to 11 kgf, which was named "plate" for such a characteristic shape of the valve cover.

With the same volume of 2.5 liters, this engine already produced 196 horsepower. The torque was raised to 245 Nm at 4.7 thousand rpm. The design scheme remained the same - it is an in-line, 6-cylinder injection engine. But unlike the M20, two camshafts have already been implemented here. Accordingly, there were 4 valves per cylinder. Remarkably, with the increase in power consumption did not increase. It remained at the same level as that of the M20V50. Acceleration to hundreds was reduced to 8.6 seconds. And the "maximum speed" has grown to 230 kilometers per hour.

М50В25 TU

This prefix meant that the engine was equipped with a variable valve timing system (vanos). This engine with a volume of 2.5 liters developed a power of 192 horsepower. The torque is 245 Nm. But what does vanos give if the characteristics of the motor remain the same? Its main task is to increase engine thrust. So, unlike the previous, vanless motor, the M50V25 TU gives out the maximum torque at 4.2 thousand revolutions. And the maximum power is already available from 5.9 thousand rpm (300 less than that of the vanless one). Thus, this engine has a high thrust and acceleration flexibility. On the move, the BMW E34 525 with this engine accelerates much more vigorously, the reviews say. The resource of this engine is more than 400 thousand kilometers. But the main problem concerns the vanos gears themselves. They require replacement after 100-150 thousand kilometers. A set of new ones costs about $ 700.

Diesel BMW E34 525 TDS

There were also diesel engines. So, if we consider the 2.5-liter line, it is worth highlighting the M51D25UL. This is a turbodiesel engine with a capacity of 116 horsepower. Its maximum torque is 220 Nm at 1.9 thousand revolutions.

The design is also in-line, 6-cylinder, with a cast-iron block. But in Russia this motor did not take root. Mechanics and motorists themselves are little familiar with him. In terms of consumption, this engine is not very economical for a diesel. For a hundred in mixed mode, it consumes 9.4 liters of fuel.

Transmission

The entire line of 2.5-liter engines was equipped with a 5-speed manual gearbox from Getarg. This transmission has proven itself on the positive side. The transmission is very reliable and “digests” all the torque from the engine well.

The clutch is dry, single disc. If we consider more powerful versions, they were equipped with an automatic transmission. But BMW's mechanics were a priority. Even the top-end E34 M5 was equipped with a manual transmission.

Chassis

The car has a multi-link suspension on both axles with a shock absorber at the rear. The suspension was distinguished by its energy intensity, thanks to which it provided the sedan with a high ride comfort. The E34 sedan is one of the most comfortable in its class. Also, the car has good brakes. There are disc mechanisms in front and behind. By the way, on larger motors, engineers changed the diameter of the disc, and sometimes the design of the calipers themselves.

A distinctive feature of the BMW E34 525 is the steering. The Servotronic was first implemented on the thirty-four. It is a system that automatically adjusts the steering force in response to vehicle speed. As she grew, the steering wheel became tighter. This provided the car with excellent road holding and handling.

Conclusion

So, we found out what features BMW E34 525 has. Despite its age, this car is still very popular. You can buy a sedan (a real legend of the 90s) on the secondary market at a price of 2.5 to 4.5 thousand dollars. Reviews are advised to purchase models without vanos, automatic transmission and hatch. These will be the most "live" and hardy specimens that will not require a lot of money for maintenance.

The M50 is a fairly popular engine that BMW produced from 1991 to 1996. in 1994, a modification appeared, the peculiarity of which was in an aluminum block. This variation was also known as the slab.

The fiftieth was installed on the e34 and e36 models. In 1992, it was equipped with a variable valve timing system called Vanos. It was installed to increase engine thrust at low and medium revs, without affecting at high revs.

Specifications and Description

The M family of the 50 series has several types of power units. It includes M50B25 and M50B20, which are remembered by many motorists as technically reliable engines. The closest modern relative is the bmw m5 e60.

Parameter	Cylinder diameter, mm	Piston stroke, mm	Engine volume, cm 2	Compression ratio	Power, h.p.	Torque, Nm	Max. rpm
Modification
BMW М50В20	80	66	1991	10,5:1	150	190	6500
BMW М50В20 TU VANOS	80	66	1991	11:1	150	190	6500
BMW M50B25	84	75	2494	10:1	192	245	6500
BMW M50B25 TU VANOS	84	75	2494	10,5:1	192	245	6500

The M50 engine was produced in only two versions - 2.0l and 2.5l.

Dignity. The M50 engine marked the beginning of a new fashion for the aggressive nature of BMW engines, which has survived to this day. Also, this model set a standard that no one violated - "1HM per 10 cm 3 cylinder volume".

The BMW M50 engine was the last in its lineup, which used a truly legendary bundle in the form of a cast iron block and an aluminum cylinder head.

Disadvantages. Despite the fact that among motorists, the BMW M50 engine is considered one of the most reliable engines for the entire production period, with improper operation such problems will inevitably appear:

1. Overheating of the power unit
2. Antifreeze leak
3. Failure of ignition coils
4. Oil leak
5. Fuel cut off

Service M 50

The M50, M50B20 and M50B25 have an excellent reputation, but do not tolerate sloppy maintenance. The conditions for their service are as follows:

1. Oil change - every 10-12 thousand km. Use only the oil recommended by the manufacturer.
2. Timing chain - its resource is on average 250-300 thousand km, after which it stretches and needs to be replaced.
3. Nozzles and candles - every 50-80 thousand km.
4. The Vanos system is repaired after 200-300 thousand km.

Repair of the M50 engine

The most common failures are the breakdown of the cooling system pump, the radiator fan drive and the failure of the oil filter.

Replacing the fan and viscous coupling

The viscous coupling needs to be replaced if the fan hub is jammed, as well as with an increased axial or diametrical clearance or with an increased oil consumption.

Withdrawal process:

1. Removing the fan shroud by removing the spacer pins at the top of the shroud
2. Unscrewing the fan mounting nut to the water pump hub
3. Direct fan removal
4. Removal of the viscous coupling is done by unscrewing four fastening bolts

Installation process:

1. Installing the viscous coupling and tightening the fastening bolts to 9 Nm.
2. Installing the fan on the pump hub and tightening the nut to 25 Nm
3. Installing the fan shroud, with both lower protrusions should go into the grooves of the radiator
4. Installing spacer clips and fixing them with pins

Removal and installation of the water pump

Many owners of BMW M50 power units complain about the frequent failure of the water pump. But, as practice shows, it is enough just to change the product yourself. Consider the pump replacement process.

Withdrawal process:

1. Disconnecting the ground wire from the battery
2. Draining the coolant
3. Removing the fan
4. Loose pulley bolts
5. Removing the V-belt
6. Loosen the four bolts of the pulley and remove the latter from the pump hub
7. Disconnecting the water pump hoses
8. Loosen the fixing bolts and remove the pump

Installation process:

1. Cleaning the mounting surface
2. Installing the O-ring
3. Installing the pump and evenly tightening the mounting bolts
4. Connecting hoses to the water pump and securing them with clamps
5. Installing the drive pulley
6. Installing and tensioning the V-belt
7. Fan installation
8. Filling the cooling system

Flushing the cooling system

Frequent heating of the motor may mean that the cooling system is clogged. Therefore, the motorist often needs to clean this unit. This can be done with auto chemicals or home remedies such as citric acid.

1. Removing the bumper, opening the lid on the reservoir and opening the radiator cap
2. Closing the lid on the tank, compressor blowing into the hole for the screw to remove air
3. Unscrewing the coolant drain plug from the block, draining the coolant
4. Filling the system with water, adding a 7-minute Hi-Gear rinse to it
5. Starting the engine and waiting seven minutes
6. Cooling down the engine and draining the fluid
7. Closing all plugs, pouring 5-6 liters of water
8. Opening one plug and running the water with a compressor
9. Repeat step 8 until clear water starts to come out
10. Filling the system with distilled water, starting the engine and warming it up to operating temperature. Cooling down the engine and draining water
11. Slow filling of the system with new antifreeze and pumping at increased speeds
12. Screwing on a new tank cap, warming up to operating temperature

Change oil and oil filter engine bmw m50

You can change the engine oil on the M50 engine with your own hands. Let's consider how to perform this operation without going to a car service and saving money:

1. Unscrewing the cap nuts
2. Removing the valve cover
3. Removing the old gasket

Output

You can change the engine oil on the M50 engine with your own hands.

Let's consider how to perform this operation without going to a car service and saving money:

1. Heating oil, unscrewing the oil drain neck
2. Unscrewing the drain bolt, draining the oil
3. Unscrewing the oil filter
4. Replacing the filter element and sealing rubber
5. Filling oil through a special neck, parallel checking its level on the dipstick

Replacing the valve cover gasket

One of the problems of engines of the 50th family, or rather the m50b20 engine, is the breakdown of the valve cover gasket. You can change this part with your own hands. Consider the sequence of actions:

1. Removing both plastic protective covers
2. Disconnecting the crankcase ventilation pipe from the valve cover
3. Disconnecting the coil wires and removing the ignition coils
4. Unscrewing the cap nuts
5. Removing the valve cover
6. Removing the old gasket
7. Cleaning the cover surface from sealant
8. Coating a new gasket with sealant and assembling everything in reverse order

Output

The M50 family replaced the M20 in the distant 1990, and had some differences, but they, in turn, made it possible to significantly increase power characteristics and reliability. The bmw M50B20 and M50B25 engine was replaced by an improved and modernized bmw m5 e60.

BMW M50B25 / M50B25TU engine

Characteristics of the M50V25 engine

Production	Munich plant
Engine brand	M50
Years of release	1990-1996
Cylinder block material	cast iron
Supply system	injector
A type	inline
Number of cylinders	6
Valves per cylinder	4
Piston stroke, mm	75
Cylinder diameter, mm	84
Compression ratio	10.0 10.5 (TU)
Engine displacement, cubic cm	2494
Engine power, hp / rpm	192/5900 192/5900 (TU)
Torque, Nm / rpm	245/4700 245/4200 (TU)
Fuel	95
Environmental standards	Euro 1
Engine weight, kg	~198
Fuel consumption in l / 100 km (for E36 325i) - city - track - mixed.	11.5 6.8 8.7
Oil consumption, gr. / 1000 km	up to 1000
Engine oil	5W-30 5W-40 10W-40 15W-40
How much oil is in the engine, l	5.75
Oil change is carried out, km	7000-10000
Engine operating temperature, deg.	~90
Engine resource, thousand km - according to the plant - on practice	- 400+
Tuning, hp - potential - without loss of resource	1000+ 200-220
The engine was installed

BMW M50B25 engine reliability, problems and repair

In 1990, the popular in-line six was replaced by a new, much more advanced and powerful, called BMW M50B25 (popularly nicknamed "Stove"), from the new M50 family (the series also included, M50B24). The main difference between the M20 and M50 engines lies in the cylinder head; in the new engine, the head was replaced by a more advanced two-shaft, 24-valve with hydraulic compensators (valve adjustment is not threatened). The diameter of the intake valves is 33 mm, the exhaust valves are 30.5 mm. Camshafts with a phase of 240/228 are used, a lift of 9.7 / 8.8 mm. And also an improved lightweight intake manifold is used.
Bosch Motronic engine management system 3.1.
The timing drive in the new M50 engines has also changed, now instead of a belt, a chain is used, the service life of which is 250 thousand km (as a rule, it runs more). In addition, individual ignition coils, an electronic ignition system, other pistons, lightweight connecting rods with a length of 135 mm are used. The size of the M50B25 nozzles is 190 cc.
Since 1992, M50 engines have received the well-known Vanos intake camshaft timing system, and such engines have become known as the M50B25TU (Technical Update). In addition, these engines use new 140 mm connecting rods and pistons with a compression height of 32.55 mm (38.2 mm on the M50B25).
The control system is replaced by Bosch Motronic 3.3.1.
These power units were used onbMW cars with index 25i.
Since 1995, the М50В25 engine began to be replaced by a new improved engine, and in 1996 the production of the М50 series was completed.

BMW M50B25 engine modifications

1. M50B25 (1990 - 1992 onwards) - base engine. Compression ratio 10, power 192 hp at 5900 rpm, torque 245 Nm at 4700 rpm.
2. M50B25TU (1992 - 1996 onwards) - added a variable valve timing system at the Vanos intake, changed the connecting rod-piston group, installed other camshafts (phase 228/228, lift 9/9 mm). Compression ratio 10.5, power 192 HP at 5900 rpm, torque 245 Nm at 4200 rpm.

BMW M50B25 engine problems and malfunctions

1. Overheating. The M50 engine is prone to overheating and tolerates it quite hard, so if the engine starts to warm up, check the condition of the radiator, as well as the pump and thermostat, the presence of air plugs in the cooling system and the radiator cap.
2. Troitus. Check the ignition coils, most often the problem is in them, as well as the spark plugs and injectors.
3. Float turns. Often the malfunction is caused by a failed idle valve (KXX). Cleaning will help revive the motor. If the problem persists, then look at the throttle position sensor (TPS), temperature sensor, lambda probe, clean the throttle valve.
4. M50 Vanos. The problem is expressed in rattling, loss of power, swimming revs. Repair: purchase of a vanos M50 repair kit.
In addition, due to their age and operating characteristics, BMW M50 engines suffer from high oil consumption (up to 1 liter per 1000 km), which does not decrease too much after overhaul. Valve cover and pan gaskets may leak, leaks through the oil dipstick are not excluded. The expansion tank also likes to crack, after which we get antifreeze leakage. At the same time, the sensors of the M50 camshaft, crankshaft (DPKV), coolant temperature, etc., cause problems from time to time.
Despite everything, the BMW M50B25 engine is one of the most reliable power units of the Bavarian manufacturer, and the bulk of the problems are caused by the age and style of operation of the engine. And even such engines roll over 300-400 thousand km, and if the motor was used in a sparing mode and was adequately maintained, then its resource can go far beyond 400 thousand km, because it is not in vain that they received a reputation of millionaires.
Buying an M50B25 engine is a good choice for swap and subsequent revision with a turbocharger. Let's talk about such decisions further.

BMW M50B25 engine tuning

Stroker. Camshafts

The easiest and fastest way to increase power using factory components is to install a long-stroke crankshaft (stroker). In M50B25 (Without vanos), a knee rises from a stroke of 89.6 mm. From the same engine, you need to buy connecting rods, connecting rod bearings, repair pistons, injectors, and main bearings from M50.
We collect (you can leave the firmware, but it's better to tune in) and drive a 3-liter M50B30, with a capacity of about 230 hp and a compression ratio of 10.
The same power can be obtained by purchasing Schrick 264/256 camshafts and adjusting the Motronic stock. As a result, we get 220-230 hp. Let's buy a cold air intake, sports exhaust and get 230+ hp.
The same camshafts on the M50B25 3.0 stroker will give about 250-260 hp.
To get maximum power from the M50B30, you need to buy Schrick 284/284 camshafts, six-throttle intake, BMW S50 injectors, a light flywheel, make cylinder head porting, buy an equal-length exhaust manifold and direct-flow exhaust. Once tuned, this M50B30 develops around 270-280 hp.
If this is not enough, you can bore a block for 86.4 mm pistons from S50B32 and get a displacement of 3.2. Buy camshafts and get about 260 hp.
The vanos M50B25 can be converted into a 2.8 liter engine by installing a crankshaft with 84 mm travel and connecting rods from M52B28. Together with the SIEMENS MS41 firmware, this will give +/- 220 hp, compression ratio ~ 11.

M50B25 Turbo

In the case when the atmospheric engine is small or the costs for its implementation are too high, you can organize a turbo version on a 2.5-liter engine. If tuning is supposed to be budgetary, then a Chinese turbo kit based on the Garrett GT35 (or another, with brains included) is your choice. Alternatively, you can find a used TD05 turbine (or another), weld the manifold, assemble all the piping, clamps, boost controller, intercooler, etc. Put everything on the stock piston, after installing a thick Cometic cylinder head gasket, 440 cc injectors, a Bosch 044 fuel pump, an exhaust on a 3 ″ pipe, an EFIS 3.1 brain (or Megasquirt), adjust it and get about 300 hp at 0.6 bar. At 1 bar ~ 400 HP
Something similar can be built by buying a compressor kit M50 and installing it on a piston stock. The compressor output will be noticeably lower than that of the turbine.
Even more power can be obtained by purchasing and installing a turbo kit on the original Garrett GT35, CP Pistons 8.5 compression, Eagle connecting rods, ARP bolts, performance injectors (~ 550 cc). With kits like this, you can increase the power up to 500 ++ HP. Similar projects can be built on a 3-liter stroker.

Diesels type M-50 F-3 (12CHSPN 18/20)

Diesel M-50 F-3 (M-400) - four-stroke, V-shaped, twelve-cylinder, mechanically supercharged, high-speed marine engine with jet fuel atomization. Available in right and left rotation models. A diesel engine of right rotation differs from a diesel engine of a left rotation in the appearance of the reversing clutch, supercharger, seawater pump, exhaust system, “as well as in the location of the fresh water pump and oil injection pump with a centrifuge. The arrangement of the units on diesel engines of left and right rotation is mirror-like.

Diesel M-50 F-3 is designed to operate on high-speed hydrofoils. The rocket-type motor ship has one engine, the meteor-type - two and the "satellite" -type - four engines. The diesel is equipped with reversible clutches, consisting of friction and gear clutches and providing rotation transfer from the diesel crankshaft to the propeller shaft (forward motion), dissociation of these shafts (idling) and changing the direction of rotation of the propeller shaft (reverse).

The operating power of the forward gear can vary depending on the purpose within the range of 368-736 kW with a corresponding change in the number of shaft revolutions within 1200 - 1640 rpm, the maximum reverse power is 184 kW at 750 rpm and the duration of operation is not more than 1 hour ...

The diesel crankcase is cast from an aluminum alloy and consists of two parts. In the upper bearing part there are seven main bearing seats with liners in which the crankshaft rotates. The split steel liners are cast in lead bronze and bored along the shaft journals. The working surface of the liners is coated with a lead-tin alloy. The platforms of the upper part of the crankcase located at an angle of 60 ° serve for the installation of two six-cylinder blocks.

The crankshaft is made of alloy steel, subjected to nitriding. It has six knees located

in pairs in three planes at an angle of 120 ° to each other. The connecting rod and main journals are connected by round cheeks. A spring shock absorber is attached to the rear flange of the crankshaft, which reduces the unevenness of torque under variable loads. Six main and six trailed connecting rods are mounted on the diesel crankshaft.

I-section connecting rods are made of alloy steel.

The upper heads of the main and trailed connecting rods are the same and have tin bronze bushings pressed into them. The lower head of the main connecting rod is split: the cover is attached to the main connecting rod by means of a wedge with two tapered pins. In the lower head of the main connecting rod, a steel liner filled with lead bronze, consisting of two halves, is installed. The trailed connecting rod is connected to the main connecting rod by means of a pin pressed into the eye of the main connecting rod.

The piston is a stamped aluminum alloy. The piston crown is shaped like a Gesselmann combustion chamber. The piston has grooves in which four piston rings are installed, of which two (upper) are compression rings, and the rest are oil scraper rings. Gas distribution valves are located in four recesses of the piston crown. The piston pin is made of alloy steel, hollow, with a hardened outer surface, pressed into the piston bosses.

Cylinder blocks - six-cylinder, are installed on the upper crankcase of the diesel engine and are attached to it with anchor pins. Each cylinder block consists of a jacket, six cylinder liners and a head. In the upper part, the sleeve has a collar, with which it rests on the surface of the groove in the block jacket. The lower belt of the cylinder bushing is sealed by five rubber rings: four serve to seal the water cavity, and the fifth (lower) prevents oil from leaking out of the upper crankcase cavity.

Figure: 1. Diesel M-50F-3

Diesel engines of the M-400 type have two six-cylinder monoblocks (the head is molded together with the cylinder block). In the monoblocks, six cylinder liners are pressed in, each of which is a connection of two pipes: an inner one made of alloy steel and an outer one made of carbon steel. The working surface of the inner tube is nitrided.

The gas distribution mechanism is driven from the crankshaft by means of an inclined gear located at the front of the diesel engine. Each cylinder has four valves - two inlet and two outlet. The valve is pressed against the seat by three coil springs. Each head of the block has two camshafts, the cams of which directly act on the valve discs, which are interconnected by cylindrical gears.

The order of operation of the cylinders on a right-hand rotation diesel engine: 1l-6pr-5l-2pr-3l-4pr-6l-1pr-2l-5pr-4l-3pr; on a diesel engine of left rotation: 1pr-6l-4pr-3l-2pr-5l-6pr-1l-3pr-4l-5pr-2l.

Fuel system. From the supply tank through the filter, the fuel enters the fuel priming pump, from which, at a pressure of 2-4 bar, it is fed through two parallel-connected fuel filters to the high-pressure fuel pump and to the injectors.

The fuel pump is a twelve-plunger pump with a double-sided shut-off and with separate suction and shut-off. The plunger diameter is 13 mm, the plunger stroke is 12 mm. Fuel supply pressure 700-1000 bar. The order of operation of the pump plungers, counting from the drive end of the roller, is as follows: 2-11-10-3-6-7-12-1-4-9-8-5.

The diesel regulator is an all-mode, indirect action, with an elastically connected cataract. Provides speed stability in the range from 500 to 1850 rpm.

The nozzle is of a closed type, with a hydraulically controlled needle. The injector nozzle has eight spray holes with a diameter of 0.35 mm, located so that when the fuel is sprayed, a cone with an apex angle of 140 ° is formed. The fuel injection pressure of 200 bar ensures that the smallest particles are atomized evenly throughout the compressed air volume in the combustion chamber.