| BMW M52 engine | |
| Production: | 1994 - 2000 |
| Configuration: | Straight-6 |
| Valvetrain: | DOHC, with VVT |
| Timing: | Chain |
| Head: | Aluminium |
| Block: | Aluminium / cast iron |
| Predecessor: | BMW M50 |
| Successor: | BMW M54 |
| Displacement: | 2- |
| Bore: | 80mm84mm |
| Stroke: | 66mm84mm |
| Fueltype: | Gasoline |
The BMW M52 is a straight-6 DOHC petrol engine which was produced from 1994 to 2000. It was released in the E36 320i,[1] to replace the M50. The BMW S52 engine is a high performance variant of the M52 which powered the American and Canadian market E36 M3 from 1996 to 1999.
In 1998, the "technical update" (M52TU) upgrades included adding variable valve timing to the exhaust camshaft.
The M52 was replaced by the M54 in the year 2000. The M52 and S52 engines were on the Ward's 10 Best Engines list from 1997 to 2000.[2]
In most markets, the M52 switched from the M50's cast iron engine block to a lightweight aluminium engine block. However, most M52 engines produced for the United States and Canadian markets (except for those used by the BMW Z3 roadster) retained the M50's cast iron engine block,[3] [4] while other cars used the new aluminum M52 block with iron sleeves.
The largest version of the M52 is 2.8 litres, compared with 2.5 litres for the M50. As per the later versions of the M50, the M52 uses variable valve timing on the intake camshaft (called "single-VANOS"). The redline remained at 6,500 rpm.
In 1998, the M52TÜ ("Technical Update") was released, adding variable valve timing to the exhaust camshaft (called "double VANOS"). Other upgrades included a new design throttle body with the ASC (traction control) motor built in and throttle cable override, revised coolant passages with an additional drain back passage and a new cooling system with push fit hoses and a separate expansion tank plus[5] a dual length intake manifold (called "DISA") and steel cylinder liners (in the aluminum block) carried over from the previous M52, these replacing Nikasil in March 1998.[6]
| Engine | Displacement | Power | Torque | Years | |
|---|---|---|---|---|---|
| M52B20 | 19910NaN0 | 1100NaN0 at 5900 rpm | 190Nm at 4200 rpm | 1994–1998 | |
| M52TÜB20 | 1100NaN0 at 5900 rpm | 190Nm at 3500 rpm | 1998–2000 | ||
| M52TÜB24 | 23940NaN0 | 1350NaN0 at 5800 rpm | 240Nm at 3600 rpm | 1998–2000 | |
| M52B25 | 24940NaN0 | 1250NaN0 at 5500 rpm | 245Nm at 3950 rpm | 1995–1998 | |
| M52TÜB25 | 1250NaN0 at 5500 rpm | 245Nm at 3500 rpm | 1998–2000 | ||
| M52B28 | 27930NaN0 | 1420NaN0 at 5300 rpm | 280Nm at 3950 rpm | 1995–1998 | |
| M52TÜB28 | 1420NaN0 at 5500 rpm | 280Nm at 3500 rpm | 1998–2000 | ||
| S52B32 | 31520NaN0 | 1790NaN0 at 6000 rpm | 325Nm at 3800 rpm | 1996–2000 |
A 1991abbr=onNaNabbr=on version was introduced in 1994. Bore is 80mm and stroke is 66mm.[7] The compression ratio is 11.0:1.
Applications:
The "technical update" in 1998 included double VANOS, which improved low rpm torque.
Applications:
2.4 L. For Thai market only. The bore is 84mm and the stroke is 72mm.
A 24940NaN0 version introduced in 1995.[8] It produces 125kW. Bore is 84mm and stroke 75mm. The compression ratio is 10.5:1.
Applications:
The "technical update" in 1998 included double VANOS, which improved low rpm torque.
Applications:
The 27930NaN0 version of the M52 debuted in 1995. It has a bore of 84mm, a stroke of 84mm and produces 142kW.[9] The compression ratio is 10.2:1.
Applications:
The "technical update" in 1998 included double VANOS, which improved low rpm torque.
Applications:
The aluminum M52 engine received criticism in some markets with high levels of sulfur in the petrol during the late 1990s. Sulfur has a corrosive effect on Nikasil and led to many early M52 and M60 engines having premature bore-liner wear.[10] [11] Countries with high sulfur fuel (such as the United States) received an iron block version of the M52 (except for the M52B28 in the Z3 which was an aluminium block), so the Nikasil problem does not apply to most M52 engines in these countries.[12]
Once the Nikasil coating was determined to be the cause of the problem, steel cylinder liners were used instead of the Nikasil coating.[13] Therefore, the M52TU engine was not affected by the Nikasil problem.[14]
| BMW S52 engine | |
| Production: | 1996 - 2000 |
| Configuration: | straight-6 |
| Valvetrain: | DOHC, with VVT |
| Head: | Aluminium |
| Block: | Cast iron |
| Predecessor: | BMW S50B30US |
| Successor: | BMW S54 |
| Fueltype: | Gasoline |
| Displacement: | 3152cc |
| Bore: | 86.4mm |
| Stroke: | 89.6mm |
The S52 is a higher performance version of the M52, which replaced the S50B30US in the post-facelift (1996-1999) North American E36 M3.
Compared to the European-spec S50, the S52 is less powerful. The S52 also shares more in common with the regular M52 engine than the S50 did with the M50, for example sharing the engine block (cast iron, as per North American M52 engines) and cylinder head. Unique to the S52 is a bore of 86.41NaN1 and stroke of 89.61NaN1 for a total displacement of 3,152 cc. Compression ratio is 10.5:1. Other upgrades over the M52 include lighter camshafts (with increased lift and duration), valve springs and the exhaust system.[15] [16]
The S52 produces 2400NaN0 at 6,000 rpm and 236lbft of torque at 3,800 rpm.[17] The S52 has a redline of 7,000 rpm while the M52 has a 6,500 rpm redline.
Applications:
