BMW M62
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| Manufacturer | BMW |
|---|---|
| Production | 1994–2005 |
| Predecessor | BMW M60 |
| Successor | BMW N62 |
| Configuration | DOHC 90° V8 |
The BMW M62 is a V8 piston engine, built in Munich, Germany. It has an aluminum block with 98 mm bore centers and two aluminum DOHC cylinder heads.
Contents |
[edit] M62
The M62 block does not use cast iron liners, which are less able to dissipate heat than aluminum. The aluminum alloy used to manufacture the M62 block contains high levels of silicon (called Alusil). The block is etched to expose the silica, creating a bearing surface in the cylinder. This was an improvement over the earlier M60 V8, that used a Nikasil cylinder wall coating, which deteriorated with the use of gasoline containing sulfur in the nickel plated combustion chambers. All M62 engines produced for the US market were built using Alusil only, which is not subject to the corrosion problem associated with Nikasil. Other countries did get the Nikasil M62 engine though.
BMW slowly stopped using Nikasil in the M62, and in 1997, they issued a service bulletin to state that the M62 engine will no longer use Nikasil from March 1997 on. This applied to all markets.
During the first 2 years of production of the M62 (From 1995 to 1997), many engines were built using Nikasil, but most of them had no issues whatsoever because they were delivered in countries were the gas was properly treated and the levels of sulfur found in them were not harmful.
Screenshot of the BMW TIS bulletin published in 1997:
Part 1:
link BMW M60/M62 Nikasil Bulletin
Part 2:
link BMW M60/M62 Nikasil Bulletin
The M62 is fitted with Sequential fuel injection (or SFI), as well as double overhead camshafts with 4 valves per cylinder. It also sports fracture-split, forged, powdered metal connecting rods. In addition, the M62TU offered on later models is fitted with BMW's VANOS VVT system.
| Engine | Code | Displacement | Power | Torque | Redline | Year |
|---|---|---|---|---|---|---|
| M62B35 | 358S1 | 3.5 L 3,498 cc (213.5 cu in) | 173 kW (235 PS; 232 hp) @ 5700 | 320 N·m (236 lb·ft) @ 3300 | 6200 | 1996 |
| M62TUB35 | 358S2 | 175 kW (238 PS; 235 hp) @ 5800 | 345 N·m (254 lb·ft) @ 3800 | 1998 | ||
| 180 kW (245 PS; 241 hp) @ 5800 | 345 N·m (254 lb·ft) @ 3800 | 1998 | ||||
| M62B44 | 448S1 | 4.4 L 4,398 cc (268.4 cu in) | 210 kW (286 PS; 282 hp) @ 5700 | 420 N·m (310 lb·ft) @ 3900 | 6100 | 1996 |
| M62TUB44 | 448S2 | 210 kW (286 PS; 282 hp) @ 5400 | 440 N·m (325 lb·ft) @ 3600 | 1998 | ||
| M62B46 | 468S1 | 4.6 L 4,619 cc (281.9 cu in) | 255 kW (347 PS; 342 hp) @ 5700 | 480 N·m (354 lb·ft) @ 3700 | 6500 | 2001 |
| S62B50 | 508S1 | 4.9 L 4,941 cc (301.5 cu in) | 294 kW (400 PS; 394 hp) @ 6600 | 500 N·m (369 lb·ft) @ 3800 | 7000 | 1998 |
[edit] M62B35
The 3.5 L (3,498 cc (213.5 cu in)) M62B35 was introduced in the 1996 535i.
Applications:
- 173 kW (235 PS; 232 hp) and 320 N·m (236 lb·ft)
- 1996–1997 E39 535i
- 1996–1997 E38 735i/735iL
- 175 kW (238 PS; 235 hp) and 345 N·m (254 lb·ft)
- 1999–2001 E38 735i/735iL
- 180 kW (245 PS; 241 hp) and 345 N·m (254 lb·ft)
[edit] M62B44
The M62B44 is a 4.4 L (4,398 cc (268.4 cu in)) M62 generation power plant with a 92 mm bore and 82.7 mm stroke. M62B44 didn't include BMW's VANOS variable valve timing system.
- 210 kW (286 PS; 282 hp) and 420 N·m (310 lb·ft) / Mechanical Throttle
-
BMW M62 B44
[edit] M62TUB44
In September 1998, BMW introduced the M62TUB44, including within it the VANOS system and an electronically actuated throttle. Each bank of cylinders included a single-stage VANOS system, and only on the intake valve timing (not the exhaust valves).
The engine design also included slightly larger mass-airflow sensor and lower flow intake plenum runners which improved lower RPM torque characteristics at the cost of some high-rpm flow. Non-"TUB" intake manifolds can be transplanted onto a M62TUB44 engine to improve high (>3400) RPM torque and power characteristics (similar in effect to the swap of OBD1 manifolds onto newer OBD2 generation M52/S52). Dinan also sells this modification under a Dinan performance package (but the BMW part numbers are equivalent to stock -B44 manifolds).
- 210 kW (286 PS; 282 hp) and 440 N·m (325 lb·ft) / Electronic Throttle -SINGLE vanos;the M5 S62 was the first BMW V8 (and only E39 V8) with dual vanos. In 2002, the power was increased from 210 kW (286 PS; 282 hp) to 216 kW (294 PS; 290 hp) while torque remained the same.
- 1998–2003 E39 540i
- 1999–2001 E38 740i/740iL
- 1999–2003 E53 X5 4.4i
- 2003–2005 Land Rover Range Rover 4.4
- 2000–2004 Morgan Aero 8 Series 1[1]
-
BMW M62 TUB44
[edit] M62B46
- The M62B46 was a 4.6 L (4,619 cc (281.9 cu in)) version producing 255 kW (347 PS; 342 hp) and 480 N·m (354 lb·ft) of torque. To increase torque and power outputs for the E53-based variant of the M62 engine, stroke was increased from 82.7 mm to 85.0 mm while bore was increased from 92.0 mm to 93.0 mm, giving an effective displacement of 4619cc.
Parenthetically, it seems odd that the 4.4-liter M62 has the same published HP of its predecessor, the 4.0-liter M60. It is well known that these engines made more power than BMW let on. There have been numerous, well-documented dynomometer runs of E39 540s with these engines (See Bimmer Forums for example) that generate between 260 and 270 HP at the rear wheels indicating that, given even a modest allowance for drive train power loss, the cars were producing crankshaft HP numbers that far exceeded what BMW published.
[edit] S62
The high-performance S62 was made for the E39 M5 and E52 Z8. It is a 4.9 L (4,941 cc (301.5 cu in)) V8 engine and is based on the same architecture as the regular aluminium block 4.4 L BMW M62 powerplant found in the E39 540i. BMW Motorsport (M) Division has extensively modified the engine for increased power and torque.
Previous M5 engines were assembled at M division headquarters in Garching, Germany but the S62 M5 engines were assembled at the Dingolfing assembly plant.
The M5's engine starts with an aluminum and silicon alloy Alusil. Cylinder linings are etched after honing to promote oil retention and reduce friction. The S62's V8 block shares the M62's basic architecture but with 94.0 mm (3.7 in) cylinder bores compared to the M62's 92.0. The stroke is increased from 82.7 mm to 89.0 mm (3.5 in) significantly improving torque. This results in a displacement of 4,941 cc (301.5 cu in). The cylinder centers are 98.0 mm apart, leaving only 4 mm of block surface between cylinders. For effective sealing with this tight cylinder spacing, BMW engineers developed new 3-layer steel head gaskets to help ensure isolation of gasoline, oil and coolant.
Based on the cylinder heads used in other BMW V8's, the M5's heads are re-jacketed for cross-flow cooling, as is customary in M division engines. The intake side of the heads also gets coolant passages. Valve adjustment is not needed, thanks to hydraulic lifters, as fitted on the US spec. E36 M3 inline-6. This is the first European-market M car to use hydraulic lifters.
The air induction system is also unique to the S62. Air is taken in at two points behind the front bumper, passes through two intake silencers and two hot-film air-mass meters, and then flows into the voluminous plenum atop the engine. From there, air courses through 230 mm-long intake runners (including the throttle housings) to the individual cylinders. The entire assembly of plenum and runners is attached to the throttle housings via a rubber/metal flange (one per bank) that acoustically and thermally decouples the plenum from the engine itself, thereby keeping the air cooler before it passes into the cylinders.
Admission of air to the cylinders is through eight individual throttle butterflies (each 48.2 mm or 1.897 in. in diameter), one for each cylinder. Other large M six-cylinder engines powering the M1, M5 and M6 models all had this feature. However, the S62 is the first BMW engine with electronically actuated individual throttles. Each throttle operates in its own housing, mounted directly above the intake port. The electronic throttle linkage (a "drive-by-wire" system) is actuated by a DC servo motor between the cylinder banks. This motor drives two shafts, one linked to each bank, opening the throttle butterflies by moving a rod that connects the four throttles on each bank. The M Driving Dynamics Control System, controlled by the Sport button on the dash, provides two settings for throttle response: normal mode and a quicker sport mode. In sport mode, throttle response is more immediate and linear. In normal mode, throttle tip-in is softer and more languid. Additionally, the throttles of cylinders 4 and 8 also have their own feedback sensors to monitor the throttles' operation. If a fault is recognized, the system switches to one of four "limp-home" modes that can allow operation at up to 100 km/h.
Bosch Motronic port fuel injection is utilized. Fuel pressure, at up to 5 bar (72.5 psi), varies according to need. The fuel regulator is also plumbed into the fuel filter. Excess fuel delivered to the filter/regulator returns directly to the fuel tank without passing through the fuel lines to the engine compartment and fuel rails. This keeps fuel temperature to a minimum.
The S62 is BMW's first V8 engine equipped with Double VANOS; a system that steplessly varies the timing of both intake and exhaust valves of both cylinder banks. The VANOS acronym refers to variable cam control or variable valve timing which in German is VAriable NOckenwellen Steuerung. Double VANOS is employed for the first time on a BMW V8 with the introduction of the S62 engine.
As on other BMW engines, the VANOS mechanisms are located at the front of the cylinder heads. The 100 bar (1,450 psi) of hydraulic pressure used to actuate VANOS is produced by two dedicated oil pumps; one for each cylinder head. Valve timing is varied over a range of 60 degrees in terms of crankshaft rotation with a wider adjustment range than that of other BMW engines.
A forged five-main bearing crankshaft with counterweights receives Mallory metal plugs for extremely fine balance. Connecting rods are forged as one piece. The caps are then fracture split for the best possible fit when being installed. Balancing pads are also placed on both small and large ends of the rods.
Piston design is unique to the S62 motor. For optimum power output, engineers designed specifically shaped cutouts in the piston crowns for the intake and exhaust valves. This requires a different piston design for each cylinder bank, rather than the usual identical design for all pistons. Pistons are cooled by two upward-firing oil jets in each cylinder. The oil jets are indexed to oil pressure; when pressure reaches 2.5 bar (36.3 psi), they begin operating. The compression ratio is 11.0:1, 10% higher than for the 4.4 L V8.
Given the 45-degree cant (from vertical) of the cylinder banks, natural return of oil to the sump might have been inadequate during extreme cornering. Thus, engineers devised a unique system to ensure effective engine lubrication at all times. In addition to the main oil (pressure) pump, there are two scavenging (suction) pumps, one for each cylinder bank. In normal and light cornering conditions, oil from the heads and main bearings flow back into the semi-dry sump at the rear of the engine via the two suction pumps. In hard cornering (0.9g or more), the Dynamic Stability Control system's lateral-g sensor switches magnetic valves to reroute oil extraction points to alternate locations (the outer sides of the heads and sump) preventing a backup of oil collecting in the outside of the head, thus avoiding potential oil starvation. This system remains active even if the driver switches off the Dynamic Stability Control.
The oil level (sump capacity of 7 litres) and temperature are monitored by a thermal sensor. A warning appears in the Check Control display if the oil level falls below a certain point. An oil-temperature gauge replaces the fuel economy gauge in the tachometer face. Oil is cooled by coolant-oil heat exchangers in the block.
The V-8's two cylinder heads are modified to provide efficient coolant flow across the head and the coolant passages are enlarged. Coolant is circulated by a larger water pump with a capacity of 380 liters per minute (83.6 gallons/min). Improvements in radiator efficiency negated any reason to enlarge it for the M5.
Other significant features of the cylinder heads include hollow camshafts of nodular cast iron for reduced inertia. The S62's 35 mm intake and 30.5 mm exhaust valves are shared with the M62 engine, but valve timing is unique. The intake cam profiles yield 10.32 mm (0.406 in) valve lift and 252 degrees total duration and the exhaust cam profiles yield 10.2 mm (0.402 in) lift and 248 degrees duration, with Double VANOS shifting their timing to vary overlap. As in other BMW V8 and 6-cylinder engines, the valves are actuated by no-maintenance bucket-type hydraulic lifters.
In place of the M62 engine's simplex roller chain driving both intake camshafts, the S62 employs a heavier-duty duplex (double roller) chain driving each intake camshaft. As in the M62, two secondary simplex chains then drive the exhaust camshafts from the intake camshafts.
Exiting the engine through double-wall stainless-steel exhaust headers (as on the M62 engine), exhaust gases then flow through one tri-metal catalytic converter per cylinder bank. There are four oxygen sensors: two ahead of the converters and two behind. Aft of the catalytic converters, the full dual exhaust system includes two resonators and four mufflers that end in four stainless-steel outlets.
The variable tachometer warning zone reminds drivers that a cold engine (especially a high-performance one) should be treated with care. When the engine is first started, the tachometer's warning zone (indicated by orange LEDs) begins at 4000 rpm. As the engine warms, LEDs are extinguished to lift the limit in increments of 500 rpm until the warning field begins at its normal 6500 rpm. The actual rpm limit is 7000.
The S62 engine produces 294 kW (400 PS; 394 hp) at 6600 rpm and 500 N·m (369 lb·ft) of torque at 3800 rpm. It is easily identified by its large central intake velocity stack chamber cover that carries the "M" logo and is further inscribed with "BMW M Power" against a simulated carbon fiber background.
Applications:
- 1998–2003 E39 M5
- 2000–2003 E52 Z8
- 1999–2006 Ascari KZ1
- 2006–Present Ascari A10
