BMW 6 Series (E24)

BMW 6-series (E24)
Overview
Manufacturer	BMW
Production	1976 - 1989 86,216 built
Designer	Paul Bracq
Body and chassis
Body style	2-door coupé
Layout	FR layout
Powertrain
Engine	2.8L−3.5L I-6
Transmission	4 or 5 speed manual, 3 or 4 speed automatic
Dimensions
Wheelbase	Template:Auto mm
Length	Template:Auto mm
Width	Template:Auto mm
Height	Template:Auto mm
Curb weight	Template:Auto kg−Template:Auto kg
Chronology
Predecessor	BMW E9
Successor	BMW E31

The BMW E24 series was the first BMW 6 Series coupé, produced by the German automaker BMW between the 1976 and 1989 model years. Replaced by the E31 chassis 8 Series coupés, the 6 Series name reappeared with the BMW E63 chassis beginning in the 2004 model year. The E24 borrowed heavily from contemporary 5-series cars (E12, later E28).

Model history

The E24 was a replacement for the CS and CSL coupés first produced in 1965. The CS 3.0 was almost changed by adding a few inches in height to make it easier for wealthier customers to get into the car. However, Bob Lutz rebelled against the decision and rough drafted an alternative version that soon became the 6 series. Production started in March 1976 with two models: the 630CS and 633CSi. Originally the bodies were manufactured by Karmann, but production was later taken in-house to BMW.

In July 1978 a more powerful variant, the 635CSi, was introduced (for the time being not available in North America and Japan) that featured as standard a special close-ratio 5-speed gearbox and a black rear spoiler.

In 1979 the carburetted 630CS was replaced with the 628CSi; this car had a fuel injected 2.8L engine taken from the BMW 528i.

In 1982 (Europe) and 1983 (US), the E24 changed slightly, with an improved interior and slightly modified exterior. At the same time, the 635CSi received a new engine, a slightly smaller-bored and longer-stroked 3430 cc six to replace the former 3453 cc engine and became available with a wide-ratio 5-speed or an automatic.

E24s produced after June 1987 came with ellipsoid headlamps instead of the halogen lamps of earlier models. The sleeker European bumpers were also discontinued. Previous cars had either a European-standard bumper or a larger, reinforced bumper to meet the US standard requiring bumpers to withstand impact at 5 mph (8 km/h) without damage to safety-related components. 1989 was the last year for the E24 with production stopping in April. The E24 was supplanted by the considerably heavier, more complex, and more exclusive E31.

M Version

The M635CSi was introduced in Europe at the Frankfurt Motor Show in 1983. It is essentially an E24 powered by the powerplant of the BMW M1 (the M88, now putting out Template:Auto PS). Most M635csi's were equipped with special metric 415 mm diameter wheels requiring Michelin TRX tires. A catalyzed, lower compression ratio version of the car with the S38 engine putting out Template:Auto PS was introduced in the U.S. in 1987. All M635/M6s came standard with a 25% rear differential. U.S. models included additional comforts such as Nappa leather power seats and a dedicated rear A/C unit with a center beverage chiller. Car and Driver tested a U.S. M6 in July 1987 and achieved a 0-60 time of 6.1 seconds, better than the BMW published 6.4 and 6.8 second times for the European and U.S. versions respectively. 4,088 M635CSis were built between 1983 and 1988 with 1,767 U.S. M6s built.

North America and Japan

While in most markets several E24 versions were usually available, markets with strict emission control regulations received only a single model (except for the M6 that was later offered additionally). This meant that in North America and Japan, BMW offered the following models :

1988 BMW M6

• 630CSi (MY 1977 through 1978½)
• 633CSi (MY 1978½ through 1984)
• 635CSi (MY 1985 through 1989)
• L6 (MY 1987 - Luxury Edition 635CSi NA-only)
• M6 (MY 1987 through 1989)

In 1977, the 6er was released in the US as the 630CSi. This was a fuel-injected version of the carburetted 630CS available elsewhere. Its 3-litre engine developed 176 horsepower (131 kW) and 185 ft⋅lbf (251 J) of torque.

In mid-model year 1978 the 630CSi was replaced by the 633CSi. US/Japan specification 633CSi cars had the M30 3.2 litre 181 hp (135 kW) engine until 1984. In 1985 the car was renamed 635CSi, displacement was increased to 3.4 litres and horsepower increased slightly to 182 hp (136 kW). The big difference, however, was torque. Whereas the 3.2 litre had 195 ft⋅lbf (264 J) at 4,000 rpm, the 3.4 litre powerplant managed 214 ft⋅lbf (290 J) at 4,000 rpm.

From model year 1983, North American and Japanese versions benefitted from the technical revisions and changes to the interior introduced elsewhere in spring or summer 1982. Its chassis was now based on the E28 and no longer on the E12. The front and rear suspension was also revised. Later a self-levelling rear suspension was added to the 635 CSi and M6 features list in 1988.

The US received its own M series E24 in 1987 called the M6. The S38 powerplant found in the US model had several modifications from the M88 powerplant in the European model, most notably: a double row timing chain, modified cam tray, different valve lengths, a slightly different cam profile, less elaborate exhaust manifold (rather than full headers), Bosch X5DC copper spark plugs (instead of Bosch Silver plugs on the M88) and the introduction of an oxygen sensor for the EFI. These changes coupled with the introduction of a catalytic converter for emission regulations reduced the output to 256 hp (191 kW). The US model also included a variety of options not found on the earlier European models, to include: heated power seats, sport tuned self-levelling rear suspension, A/C cooled ice box between the rear seats, A/C vents for rear seat occupants, sunshade for rear occupants and an 8 speaker "premium" sound system.

In 1988, the US E24 was now available with the newest version of the M30, the 3.4L (first used in the E32 735i). Even though the intake manifold states 3.5 it's technically a 3.4 (3430cc) like the previous 3.4. This engine had an increased compression ratio, and updated Motronics/DME. The result was 208 hp (155 kW) and 225 ft⋅lbf (305 J) torque. In effect, this engine was identical to the catalyzed version newly available in Germany and other markets.

Technical data BMW 628CSi-M 635CSi (E24) (except North America and Japan) (Manufacturer's figures except where stated)

BMW	628CSi	630CS	633CSi	635CSi	635CSi	M635CSi
Produced:	1979 - 1987	1976 - 1979	1976 - 1982	1978 - 1981	1982 - 1989	1983 - 1989
Engine:	6-cylinder-inline engine (four-stroke), front-mounted
Bore x Stroke:	86 mm x 80 mm	89 mm x 80 mm	89 mm x 86 mm	93.4 mm x 84 mm	92 mm x 86 mm	93.4 mm x 84 mm
Displacement:	2788 cc	2985 cc	3210 cc	3453 cc	3430 cc	3453 cc
Max. Power @ rpm:	Template:Auto PS @ 5800	Template:Auto PS @ 5800	Template:Auto PS @ 5500	Template:Auto PS @ 5200	Template:Auto PS @ 5200	Template:Auto PS @ 6500
Max. Torque @ rpm:	Template:Auto Nm @ 4200	Template:Auto Nm @ 3500	Template:Auto Nm @ 4300	Template:Auto Nm @ 4000	Template:Auto Nm @ 4000	Template:Auto Nm @ 4500
Compression Ratio:	9.3: 1	9.0 : 1	9.3 : 1	9.3 : 1	10.0 : 1	10.5 : 1
Fuel feed:	fuel injection Bosch L-Jetronic	single downdraft carburetor Pierburg 4A1	fuel injection Bosch L-Jetronic		fuel injection Bosch Motronic
Fuel tank capacity:	70 L (18.5 US gal; 15.4 imp gal)
Valvetrain:	12 valves, SOHC, duplex chain					24 valves, DOHC, duplex chain
Cooling:	Water
Gearbox:	4-speed manual, from 1979 5-speed manual (wide- or close-ratio) on request 3-speed automatic, from 1983 4-speed automatic rear wheel drive					5-speed manual rear wheel drive
Electrical system:	12 volt
Front suspension:	McPherson axle, coil springs, stabilising bar
Rear suspension::	Trailing arms, struts, coil springs, stabilising bar
Brakes:	disc brakes (Ø front 280 mm, rear 272 mm), power assisted, from MY 1984: ABS
Steering:	ZF recirculating ball steering, power assisted
Body structure:	Sheet steel, unibody construction
Dry weight:	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg
Loaded weight:	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg	Template:Auto kg
Track front/ rear:	Template:Auto mm Template:Auto mm	Template:Auto mm Template:Auto mm	Template:Auto mm Template:Auto mm	Template:Auto mm Template:Auto mm	Template:Auto mm Template:Auto mm	Template:Auto mm Template:Auto mm
Wheelbase:	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm
Length:	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm
Width:	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm
Height:	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm	Template:Auto mm
Tyre/Tire sizes:	195/70VR14	195/70VR14	195/70VR14	195/70VR14	205/70VR14	220/55VR390 or 240/45VR415
Top speed:	Template:Auto km/h	Template:Auto km/h	Template:Auto km/h	Template:Auto km/h	Template:Auto km/h	Template:Auto km/h
Fuel Consumption (estimates):	Template:L100km	Template:L100km	Template:L100km	Template:L100km	Template:L100km	Template:L100km

External links

• Sharknose (German website)
• Bigcoupe.com - Largest resource for the BMW E24