BMW M52TUB20, M52TUB25, M52TUB28 engines

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M52TUB20
M52TUB25
M52TUB28

The M52 series are BMW gasoline engines with an in-line configuration of 6 cylinders and two camshafts (DOHC).

They were produced from 1994 to 2000, but in 1998 there was a “technical update” (technical update), with which the dual VANOS system was introduced to existing models, which regulates the timing of the exhaust valves (dual gas distribution system). In the lists of the best 10 Ward engines for 1997, 1998,1999, 2000 and 52, the MXNUMX regularly appeared and did not give up their positions.

The engines of the M52 series received an aluminum cylinder block, unlike the M50, which was made of cast iron. In North America, cars were still sold with these engines in a cast-iron block. The upper speed limit is 6000 rpm, and the largest volume is 2.8 liters.

Speaking of the 1998 technical update, there are four main improvements:

Vanos valve timing system, which will be discussed in more detail later;
Electronic throttle control;
Double-sized Variable Geometry Intake Valve (DISA);
Redesigned cylinder liners.

M52TUB20

This is a modified M52B20, which, due to the improvements received, like the other two, has more traction at lower revs (peak torque is 700 rpm lower). The cylinder bore is 80mm, the piston stroke is 66mm, and the compression is 11:1. Volume 1991 cu. cm, power 150 hp at 5900 rpm - the continuity of generations in these characteristics is noticeable. However, the torque is 190 N * m, like the M52V20, but at 3500 rpm.

Used on cars:

BMW E36 / 7 Z3 2.0i
1998-2001 BMW 320i/320Ci (E46 body)
1998-2001 BMW 520i (E39 body)

M52TUB25

The piston stroke is 75 mm, the cylinder diameter is 84 mm. The original B25 2.5-liter model exceeds its predecessor in power - 168 hp. at 5500 rpm. The modified version, with similar power characteristics, produces the same 245 N * m at 3500 rpm, while the B25 reached them at 4500 rpm.

Used on cars:

1998-2000 E46323i, 323ci, 325i
1998-2000 E39523 XNUMXi
1998-2000 E36/7Z3 2.3i

M52TUB28

The engine displacement is 2.8 liters, the piston stroke is 84 mm, the cylinder diameter is 84 mm, the crankshaft has an increased stroke compared to the B25. Compression ratio 10.2, power 198 hp at 5500 rpm, torque - 280 N * m / 3500 rpm.

The problems and disadvantages of this ICE model are generally similar to the M52B25. At the top of the list, he has overheating, which often leads to malfunctions of the gas distribution mechanism. The solution to overheating is usually cleaning the radiator, checking the pump, thermostat, radiator cap. The second problem is oil consumption in excess of the norm. In BMW, this is, in principle, a common problem, which is associated with non-wear-resistant piston rings. In the absence of development on the walls of the cylinders, the rings can simply be replaced and the oil will not leave more than prescribed. Hydraulic lifters on these engines "like" to coke, which leads to misfiring.

M52tuB28

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Used on cars:

1995-1999 E36328 328i, XNUMXis
1995-1998 E39528 XNUMXi
1995-1998 E38728 728i, XNUMXiL
1997-1998 E36/7Z3 2.8

The VANOS system is very sensitive to the operation of the engine and in the event of unstable revolutions, uneven operation in general or a drop in power, it wears out a lot. To solve it, you need to have a system repair kit.

Unreliable crankshaft and camshaft position sensors often cause the engine not to start, although outwardly everything is fine. The thermostat tends to leak, and in general the resource is lower than that of the M50.

Of the advantages, it can be noted that these three engines are not particularly sensitive to the quality of gasoline. Tuning them is usually not recommended, as well as buying for a swap, since they are already simply old. However, for those who are persistent in their desire, there is a proven way - to install the intake manifold M50B25, camshafts from S52B32 and chip tuning. Such tuning will raise the power to a maximum of 250 hp. Another obvious option is boring up to 3 liters, accompanied by the purchase of an M54B30 crankshaft and cutting the piston by 1.6 mm.

Installing a turbine on any of the described engines is a completely adequate way to increase power. For example, an M52B28 with a Garrett turbine and a good processor setup will produce almost 400 hp. with a stock piston group.

The tuning methods for the M52V25 are somewhat different. Here it is necessary to purchase, in addition to the intake manifold from the “brother” M50V25, also a crankshaft with M52V28 connecting rods, as well as firmware. Camshafts and exhaust system are better to put then S62 - without them, it will not budge when tuning. So, with a volume of 2 liters, you will get more than 200 hp.

To raise power on the smallest 2-liter engine, you will need either a bore to a maximum of 2.6 liters or a turbine. Bored and tuned, he will be able to give out 200 hp. Turbocharged with the help of a special turbo kit will eventually be able to squeeze out 250 hp. at 2 liters of working volume. The Garrett kit can be replaced by the Lysholm, which will also give a power increase within the same limits.