Mercedes-Benz R107

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The Mercedes-Benz R107 automobiles were produced from 1971 through 1989. They were sold under the SL-Class and SLC-Class model names, respectively. The R107 replaced the W113 SL-Class in 1972 and was replaced by the R129 SL-Class in 1989.

The R107 took the chassis components of the mid size Mercedes-Benz W114 model and mated them to the larger engines from the S-Class. The W 107 chassis is sometimes referred to as "R 107" for "Reihe" (series). The US models built on the 107 chassis were the 350 SL, 380 SL, 450 SL, and the 560 SL. (One of the European models of the 107 family was a "280 SL". This should not be confused with 280 SL of the earlier 113 chassis.)

The SL variant was a 2-seat convertible. It proved popular, especially in the United States where they were sold at a very high price.

The SLC (technically C107) derivative was an SL stretched 10 inches, a 2 door hardtop coupe, with usable rear seats. It was replaced earlier than the SL, with a much larger model, the 380SEC. It was aimed at the same market as more exotic machines like the Jaguar E-Type and Citroën SM.

The 107 chassis had the longest run of any Mercedes chassis, 18 years from 1971 to 1989. Some 237,000 107 chassis SL's were built. About two thirds were sold in the US. These 107 cars are larger, heavier and more costly than the previous generation W113 cars.

Prices increased dramatically over the years. The earliest 107, the 1971 350 SL, sold for about $11,000. Eighteen years later, the last 107 model, the 560SL, sold for about $64,000.

Production of the first R107 car, the 350 SL, started in November 1970 alongside the last of the W 113 cars. When the first 350's were exported to the US, because of the strict horsepower robbing emission requirements, the US 350's were shipped with low compression 4.5 liter engines. A Mercedes-Benz service person said that when these cars came in for service, his shop replaced 350 SL model badges with 450 SL badges.

From 1974 until the end of production, the front and rear bumpers of the U.S. mofel R107 grew out 8 inches on each end to comply with U.S. regulations.

The 450 SL was produced until 1980. Some 450 SLs suffered from vapor lock and hard re-start because of the position of the catalytic converter.

Next was the 380 SL built from 1981 to 1985. The 380 SL was the least powerful of the US imported R107 roadsters. This engine came with a single row timing chain. These models were plagued with chain failure problems and the problem was corrected by Mercedes-Benz, free of charge. Some models, however, escaped retrofit and may at some point fail as a result.

The more powerful 500SL with 5.0 liter engine, produced from 1980-1989, was not available in the U.S. through Mercedes-Benz and was popular in "gray market" import before the arrival of the 560SL (only made for the USA and Australian market) in 1986-1989.

Despite the larger 5.6 liter engine of the 560SL, the 500SL is recorded as being the fastest production 107 produced (mostly because of the lack of emission restraints.) The 500SL was published by Mercedes-Benz as having 0-60 times of 7.4 seconds for a top speed of 140 mph. Torque for the 500SL is 297@3200 rpm and for the 560SL 279@3250 rpm. The 500SL was not available in the U.S. or Australian markets through Mercedes Benz dealers.

The last 107 made, a 1989 500SL painted Astral Silver, resides in the Mercedes-Benz museum in Stuttgart, Germany.

[edit] The 5-Litre SLC Rally Cars

The following article appeared in the June/July 2005 issue of "Das Rundschreiben", the magazine of the Mercedes-Benz Club (NSW) Inc.

From the mid 1950s to the mid 1960s Mercedes-Benz cars were seen in rally competition, initially as the legendary 300SL, then the 220SE, the 230SL and finally the 300SE. A period of around twelve years then elapsed before Mercedes-Benz cars were again seen in rallies.

In 1977 a crew comprising Andrew Cowan, Colin Malkin and Mike Broad were victorious in a W123 series 280E in the 18,000 km London to Sydney Rally and a similar 280E of Fowkes and O'Gorman came in second. The following year the 280E of Zasada and Krupa finished sixth in the African Safari Rally.

Daimler-Benz realised that its cars had the necessary durability for rallies and that with more power they could achieve further success. While other manufacturers were rallying small to medium sized cars, Daimler-Benz decided that following their experiences with the 280E, the coupe version of their 107 series was the car to use. The "SL" in SLC was supposed to stand for "sports-light" but this was not an accurate description of the long and heavy SLC coupe, at the time the flagship of the Mercedes-Benz range aimed at the upper end of the luxury market. With V8 engines it was however a fast tourer. The fixed roof of the SLC added to the body rigidity of the SL and the superb handling, together with the comfort of the long wheelbase coupe, meant that crews would suffer the minimum of fatigue over long rallies.

The 107 series had been released in 1971 with the 200 horsepower (147 kW) 3.5-litre M116 V8 initially as the 350SL 2-seat roadster and then as the 350SLC 5-seat coupe. Subsequently the 225 hp (165 kW) 4.5-litre M117 V8 was added to the range in the 450SL and 450SLC with the 185 hp (136 kW) 2.8-litre twin-cam M110 six-cylinder from the 280E added later still. In 1978 a new all-alloy 240 horsepower (177 kW) V8 engine of 5,025 cc was developed specifically for the rally version of the SLC. Previously all 107 models used engines with alloy cylinder heads on cast iron cylinder blocks. Together with a lightweight aluminium bonnet and boot lid, the new engine also assisted in reducing the substantial weight of the big coupe and the resulting car became known as the 450SLC-5.0. Despite the light alloy block, the 5-litre engine retained the M117 designation and the remainder of the rally version of the 450SLC-5.0 differed little from the standard 450SLC, including the 3-speed torque converter automatic transmission.

The month-long 30,000 km 1978 Vuelta America del Sud (Tour of South America) was chosen as the debut event for the SLC rally car. A 450SLC-5.0 crewed by Andrew Cowan and Colin Malkin won the rally with second place going to Zasada and Zembruski also in an SLC, third to Fowkes and Kaiser in a 280E and fourth to Makinen in the remaining SLC. Only about one third of all the entered cars survived the gruelling rally, however all four SLC and three of the four 280E Mercedes entered completed the event.

For 1979 the 450SLC-5.0 was homologated as a Group 4 rally car with power being increased to around 300 hp (220 kW) and further weight reductions resulted from stripped-out interiors. Three-speed automatic transmission was retained as it was considered the only Daimler-Benz unit capable of withstanding the torque of the V8. Massive factory support under the leadership of Eric Waxenberger backed the effort behind several entries in the 1979 World Rally Championship. Three each 450SLCs and 280Es were entered in the African Safari Rally and SLCs driven by Bjorn Waldegard and Hannu Mikkola led for much of the event. Mikkola and Hertz finished a close second with Cowan and Syer in a 280E in fourth and Waldegard sixth. Greater success was achieved with a clean sweep of the 5,500 km Bandama (Ivory Coast) Rally with four 450SLC-5.0s driven by Mikkola, Waldegard, Cowan and Preston taking positions 1, 2, 3 and 4 respectively.

Following the 1978 and 1979 successes, an even greater effort went into the 1980 season. The Portugal Rally resulted in a best of only fourth place for Waldegard and Thorszelius and it was becoming obvious the big SLC was not so suited to the shorter and tighter European rallies. In the 5,300 km Safari Rally where success was expected, rear suspension failures saw a best of third place to Vic Preston Junior in a 450SLC-5.0 using the newly introduced four-speed automatic transmission. In the Acropolis Rally the power of the 5 litre SLCs resulted in shredded tyres on the rocky roads with the highest placing again going to Preston this time down in fourteenth place.

For the Rally of Argentina engine output increased to 340 hp (250 kW) despite a slight reduction in displacement to 4,975 cc. The cars became known as a 500SLC and were now homologated as Group 2. Mikkola and Hertz managed second place however two other 500SLCs suffered broken drive shafts. In the Rally of New Zealand Mikkola finished third and Waldegard fifth. In the same event Cowan suffered rear brake problems. Following a call over the radio, a helicopter was soon seen flying with an entire replacement rear axle assembly slung underneath, such was the level of factory support. The final event contested for 1980 was the Ivory Coast Rally better suited to the big fast SLC. The rate of attrition across all entrants was huge including Cowan who crashed. A total of just eleven cars finished with first to Bjorn Waldegard, second to Jorge Recalde and fifth to Vic Preston, all in 500SLCs.

Not entering every event for the 1980 season resulted in Mercedes finishing fourth overall in the championship. Mercedes recruited winning driver Walter Rohrl who had been driving for Fiat in preparation for the following year. With the realisation that the SLC was just too big for the European rallies, plans were to use the similar but shorter 500SL for 1981. This was never to eventuate and the 1980 champion was left without a drive for 1981. Daimler-Benz again had a break from motor sport for a few years until the introduction of the W201 series 190E 2.3-16 destined for circuit racing, but that is another story.

The 350 and 450SLC (like the 350 and 450SL) had been discontinued in 1980 with the introduction of the 380 and 500SLC. The 280, 380 and 500SLC were discontinued in 1981 with the introduction of the 126 series 380 and 500SEC coupes. A total of 62,888 SLCs had been manufactured over a ten year period of which just 1,636 were the 450SLC-5.0 and 1,133 were the 500SLC. Both these models are sought by collectors today. The SLC remains the only fixed roof Mercedes-Benz coupe based on a roadster rather than a sedan. Even today, an SLC in good mechanical condition still gives a mix of good performance, superb handling, comfort and safety, making it is easy to realise why they were a successful rally car. Following the discontinuation of the SLC, the 107 series continued initially as the 280, 380 and 500SL and then finally as the 300, 420, 500 and 560SL until 1989. This eighteen-year run makes the 107 series the longest running series produced by Daimler-Benz.

Vehicles:

• 1972 Mercedes-Benz W107 350SL V8
• 1972–1980 450SLC V8
• 1974–1981 280SLC Straight 6
• 1971–1980 350SLC V8
• 1973–1980 450SL V8
• 1975–1985 280SL Straight 6
• 1980–1981 380SLC V8
• 1978–1981 500SLC V8 (Created for a Rally Version, initially known as the 450SLC-5.0, up to 1979, then as the 500SLC)
• 1981–1989 500SL V8
• 1981–1985 380SL V8
• 1986–1989 300SL Straight 6
• 1986–1989 420SL V8
• 1986–1989 560SL V8 (USA and AUSTRALIAN market only)

Mercedes-Benz road car timeline, 1946-1970s  v • d • e																																	Next ->
Class	Type	1940s				1950s										1960s										1970s
		6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9
4-cylinder	Sedan	W136/W191							W120/W121								W110								W115
	Roadster										W121
6-cylinder	Sedan						W187			W105/W180/W128							W111								W114								W123
	Coupé						W187					W180/W128
Large	Sedan						W186/W189								W111				W108/W109							W116
	Luxury							W188									W112
	Limousine						W186/W189										W112				W100 (600)
Sports	Roadster									W198										W113									R107