BMW M30B35MAE engine

Serial engine M30 from BMW concern is one of the most popular branches of internal combustion engines of the German concern. This power unit is made in various modifications. All units received 6 cylinders and 2 valves on each of them. Installed this internal combustion engine on all cars of Bavaria Motors, which were produced at the time from 1968 to 1992. Despite the fact that this engine is considered obsolete, it powers tens of thousands of cars that are on the go, even as of 2019. Car enthusiasts, car service stations, and collectors consider this engine to be one of the most successful in BMW’s engine building history. All because of the unpretentiousness in maintenance and repair, the absence of any serious problems with the powertrain (however, they were and about them we will write below) and an incredible huge resource of operation. All BMW cars from 5 to 7 series of the first and second generation, which were produced from 1982 to 1992, received the M30 engine. It has a wide range of modifications. Modified versions were characterized by a turbocharger, which is installed in the cars of the sixth and seventh generations. Today we will talk about the model with the largest volume in the entire series. 3.43 liters, which is equipped with a turbine.

Different versions of this engine are available:

1. Motors equipped with catalytic converter, low compression pistons (CR = 8) and Bosch Motronic 1.0. Power output of the M30B35 is 185 hp at 5400 rpm.
2. Engines not equipped with catalytic converter and new pistons (compression ratio 10: 1). Their output is 218 horsepower at 5500 rpm.
3. Version with catalytic converter, with different pistons (compression ratio 9: 1) and with Bosch Motronic 1.3. Such engines have an output of 211 hp at 5700 r / min. In 1992, the BMW M30B35 was replaced by a more modern V8 – M60B40 .

M30B35MAE engine specifications

Advantages

Speaking of benefits, M30 engines are some of the best and reliable powertrains that have impressive mileage that modern cars don’t have. The powerplant has a posh tuning range, with torque that starts at 2200 rpm. Which for the second half of the 20th century were incredible numbers. Machines on these internal combustion engines are able to run more than five hundred thousand kilometers, without serious breakdowns, not counting those mentioned above. But here, as luck would have it. As we said at the beginning of the article, there are a lot of cars in Russia that use this internal combustion engine and are still on the move. Another plus can be emphasized the complete study of the design of this internal combustion engine. At a glance, you can pay attention to this or that symptom and immediately make a verdict. But very often there are problems with the fact that the necessary components are simply not available, due to the fact that the engine has long been unsupported and not produced. Therefore, delivery to certain regions of Russia can take from several weeks to as long as months.

Disadvantages

As for the problems with the internal combustion engine, like all M30 motors, it is inherent to it with overheating, cracks in the cylinder block and banal old age. But despite this, technical miscalculations of the car are practically absent. But still it is possible to allocate certain disadvantages. The first thing that the owners of this powertrain face is banal overheating. If you find an increased temperature of engine operation, you need to immediately check the cooling system. Otherwise, the main cylinder block will behave. Pay your attention to the radiator. It can be banally clogged. It is also necessary to check the thermostat and pump. And also check for the formation of air plugs in the cooling system, after you have replaced the antifreeze. Another issue could be a crack in the cylinder block. This defect forms in the threads of the bolts. If you find a serious drop in antifreeze level, emulsion, with a complete engine oil change, you need to pay close attention to this, otherwise – could lead to a major overhaul. BMW has replaced powerplants under warranty with the defect we mentioned above. The problem was the grease that was in the wells. The craftsmen who assembled these internal combustion engines did not completely remove the fluid. As a result, it had a destructive effect on the entire engine. In order to solve this problem it is necessary to replace the cylinder block. This nuisance is rarely repaired.  It is also necessary to take into account the fact that the entire line of m30 engines, at the time of the beginning of 2019 are morally and technically obsolete. These power units have not been produced for a long time, their power reserve is elementary rolled out. Every time there will be problems, which is associated with the aging of parts. That leads to failures that occur in the work of the mechanism of gas distribution, valves wear out, in the cylinders are formed gaps. Not to mention a faulty crankshaft and constantly breaking bushings.

Most often there are problems with the valve. You will not be able to adjust them properly. If this happens, you need to buy a set of guide bushings, replace the rocker arm eccentrics and the worn valves. Sometimes there are problems with the MAF sensor. For its time, the BMW M30B35 is a great engine and can go over 500,000 kilometers without major repairs.

Technical specifications

In order for the powertrain to develop a maximum output of 290 horsepower, it is necessary to accelerate the engine to 4000 rpm. Maximum torque reaches a mark of 305 Newtons per meter. BMW 635, 735, 535, later year of release have this engine under the hood. We are talking about BMW 635, 735, 535, later years of production – from 1988 to 1993. This is the most modified engine from the M30 range. So, the power unit M30B35LE was similar to develop power up to 220 horsepower. About this internal combustion engine you can read on our portal. And the torque was in the region of 175 Newtons per meter when reaching 4000 rpm.

The modification that will be discussed today is the M30B35MAE. This version was equipped with a supercharger-turbine and developed useful power up to 252 horsepower. BMW motorists worked on the maximum torque and moved it to lower revolutions. The driver only needs to develop 2,200 rpm to get the maximum torque output to the rear wheels of 375 Newtons per meter. Let’s talk about the technical specifications. Our powerplant has an impressive displacement of 3.4 liters. This is a modified version of M30, only with bored cylinders. M30B35MAE received the diameter of each cylinder – 92 mm, and 6 mm increased stroke of the piston. Compared to the M30, there was 80 mm. The cylinder head also underwent significant changes. It received one camshaft, which had 12 valves. Every 7-10 thousand kilometers it is necessary to visit the service station of the car in order to adjust the thermal gaps, because this power unit was not installed hydrocompensators.

Another interesting feature of the M30 engine range is that you can bore the cylinder block in the garage and turn the M30B30 engine into an M30B35. To do this, you need to bore the cylinder block, buy new pistons and connecting rods. This is the easiest in tuning the internal combustion engine from BMW. As for the technical characteristics, it is difficult to designate the exact value. After all, there were several variations of this internal combustion engine. Earlier versions had a compression ratio of 8 units and did not have catalysts. In turn, a little later came the engine, which had 9 units of compression and had a capacity of 211 horsepower.

Let’s talk about the dry tactical-technical characteristics of this power unit. The exact volume of the engine is 3430 cubic centimeters. And the maximum power is presented in modifications from 240 to 252 horsepower. Maximum torque reaches a value of 380 Newton per meter if you spin the power plant to 2200 revolutions. The engine uses 92 octane gasoline. The engine has two valves per cylinder. In order to squeeze out the maximum 252 horsepower, (185 kW), the engine must be accelerated to 5000 rpm. This version uses a turbo. The compression ratio is 8 units, the piston strokes 86 mm. The engine is installed on the BMW 7 series, which was produced from May 1983 to August 1986. This is the first generation in the e23 body, restyling, sedan.

Chip Tuning

As for tuning, there are several options to unlock the M30B35 powertrain. Even in early 2019, you can find components on various sites that can add about 30 horsepower and fully unlock the potential of the internal combustion engine. But you can get even more if you enlarge up to 98 mm, bore the cylinders. As a result – you can squeeze out a maximum volume of up to 4 liters. Forged pistons will complete this composition. But for the sake of truth, it is worth paying attention to the fact that the cost of work will be several times the price of the engine itself. You can also buy some Chinese turbo-kit with a capacity of 0.8-1 bar – with its help you can raise the power up to 400 hp, but only for 2-3 thousand kilometers, as turbo-kits do not live long.

There are many different parts available for the BMW M30. If you have a burning desire to make a powerful M30B35, you should start by getting the motor into a normal, running condition. After that, there are two ways: buy stroker kits or new cams.

To make a 4 liter M30B35 you need to buy a 98mm stroke crankshaft, short connecting rods, increase the cylinder bore to 93.5mm and forged pistons. If you increase the cylinder bore to 95 mm, you get 4.2 liters.

Second way: You need to shave the cylinder head to increase the compression ratio to ~11. After that, you need to significantly modify the cylinder head. And also get into the brains of the car which need to be adjusted to match the new modifications. As a result, the powertrain will give about 240-250 horsepower. You will get additional power by buying forged pistons, lightweight connecting rods and a set of separate S38 throttle bodies.

This engine is installed on the following models:

BMW 7-Series (E23)