BMW S52 Engine
|Also called||BMW S52/S52B32|
|Cylinder block alloy||Cast-iron|
4 valves per cylinder
|Piston stroke, mm (inch)||89.6 (3.53)|
|Cylinder bore, mm (inch)||86.4 (3.40)|
|Displacement||3152 cc (192.3 cu in)|
|Power output||176 kW (240 HP) at 6,000 rpm
|Torque output||320 Nm (236 lb·ft) at 3,800 rpm
|HP per liter||76.1
|Weight, kg (lbs)||141 (311)|
|Fuel consumption, L/100 km (mpg)
|for E36 M3 US
|Oil consumption , L/1000 km
(qt. per miles)
|up to 1.0
(1 qt. per 750 miles)
|Recommended engine oil||0W-30
|Engine oil capacity, L (qt.)||5.5 (5.8)|
|Oil change interval, km (miles)||5,000-10,000
|Normal engine operating temperature, °C (F)||~90 (195)|
|Engine lifespan, km (miles)
-No life span loss
|The engine is installed in||BMW M3 E36
Then the production of S50B30 ended the European market entered by the S50B32, but for the North American market it wasn’t delivered. BMW M3 E36 with own engine – S52B32 was sold there. This motor hasn’t any relation with S50 Euro. The American S52 is a leader of the M52 series (also included M52B20, M52B25 and M52B28) and represents the modified M52B28.
6-cylinder BMW S52 based on M52 US, which cylinder block is cast-iron. Diameter of cylinders increased to 86.4 mm in it, and also used forged S52 crankshaft, with a piston stroke of 89.6 mm. S52 used the connecting rods with length equal to 135 mm, and the compression height of the piston is equal to 31 mm. It helped to increase displacement to 3.15 liter.
Cylinder head from M52 used with the following changes: lightweight tappets, springs, the new lightweight camshafts (their specs: duration 252/244, lift 10.2/10.2 mm). Installed new head gasket. Intake system with one throttle body as on M52. Exhaust system is a little more perfect. The firing order for the BMW S52 engines is 1-5-3-6-2-4. The stock size of fuel injectors S52 – 250 cc/min.
All this allowed to get 240 horsepower at 6,000 rpm and a torque 320 Nm at 3,800 rpm.
The electronic control unit of S52B32 – Siemens MS41.1.
This engine used on BMW M3 E36 cars and Z3M made for the US and Canada.
In 2000 BMW replaced with the real M-engine – BMW S54.
BMW S52 engine problems and malfunctions
S52 is not too different from usual M52. Its most widespread malfunctions are similar to M52. You can learn more about HERE.
S52 performance upgrades
The main problem of S52 is intake manifold with narrow runners (30% narrower than the M50). This motor designed for low and mid revs. For going faster you need the following performance parts: an M50 intake manifold, cold air intake or Turner Motorsport Stage 2 kit. These mods will increase power to 270 HP.
If you add Schrick 264/256 camshafts, power will increase to 280 horsepower. Setting headers and performance exhaust system, your S52 will show about 290 horsepower S52 became closer to Euro S50B30 ITB.
All these modifications is the easiest and cheapest way to improve your BMW S52. You can also buy high compression pistons, connecting rods, more aggressive camshafts, made head porting, try to install ITB (individual throttle bodies), but it’s not easy and not profitable.
S52 Turbo. Supercharger
It is real to get 350 horsepower on S52 enough to buy a supercharger kit. Most of these proposals develop max boost up to 6 psi (0.4 bar) and allow you to get extra 110 HP. Stock internals BMW M3 E36 S52B32 is able to hold up to 400 horsepower. and temporarily up to 450-500 horsepower (as lucky). You just need to buy a kit and put it on a stock engine and drive until you get bored.
After a while 350 horsepower will seem to you a little you want to take something special. For this you need to remove the supercharger and buy H-beam rods, low compression pistons (CR=8.5-9), MLS head gasket and ARP studs. This kit will reduce the compression ratio and prepare your S52 for bigger power. Next, you need to buy a Precision 6266 turbocharger, turbo manifold, intercooler, wastegate, blow-off, fuel pump (e.g. Walbro 400), fuel pressure regulator. Also you need a performance exhaust system 3.5″ and Megasquirt ECU (or other aftermarket ECU). After collecting everything and adjusting, you will get over 600 horsepower.