Mercedes Service and Repair Redwood City - History of the Mercedes 190e 16v Cosworth - Bosch European Redwood City - 650-368-3000

 

The 190e 16v was really a first for Mercedes and it still has some features that we've never really seen before or since such as a high revving 4 cylinder 16v engine, a factory fitted body kit and a dog leg gear box. Add this to the relative rarity of the 2.5 (only 7000 or thereabouts where sold in the UK) and the fact that these cars were built at a time where Mercedes build quality really was at its highest and you'll see what the appeal is....these pages cover the development and history of the Mercedes Benz 190e 2.3 16v, Mercedes Benz 190e 2.5 16v, Mercedes 190e Evolution, Mercedes 190e Evolution 1 and Mercedes 190e Evolution 2 models.

The Story
Back in the late 1970s, Mercedes competed in rallying with the big V8-powered Coupés of the R107 Series, mainly the light-weight Mercedes 450 SLC 5.0. Mercedes wished to take the 190E rallying, and asked British race car engineering company Cosworth to develop an engine with 320 bhp for the rally car.

This project was known as project "WAA" by Cosworth". During this time, the Audi Quattro with its all wheel drive and turbocharger was launched and made it apparent that the 2.3-16v would not be competitive. With a continued desire to compete in high-profile motorsport with the 190, and also now an engine to do it with, Mercedes turned to the Deutsche Tourenwagen Meisterschaft (DTM) motorsport series instead. Cars racing in this championship, however, had to be based on a roadgoing model. Mercedes therefore had to put into series production a 190 fitted with a detuned version of the Cosworth engine.

This high performance model was known as the 190E 2.3-16, and debuted at the Frankfurt Auto Showin September 1983, after its reputation had already been established. Three cars, only slightly altered in cosmetic bodywork, had previously set three world records in August at Nardo, Italy, recording a combined average speed of (138.06 mph) over the endurance test of 50,000 km, and establishing twelve international class endurance records.

The Engine
The Cosworth engine was based on the 2.3 8 valve 136 bhp unit already fitted to the 190- and E-class series cars. Cosworth had redeveloped the entire engine, including fitting it with a new cylinder head, which was developed by Cosworth engineers "applying knowledge we've learnt from the DFC and BDA". It was made from light alloy using Coscast's unique casting process and brought with it dual overhead camshafts and four valves per cylinder, meaning 16 valves total which were developed to be the "largest that could practically be fitted into the combustion chamber".

In roadgoing trim the 190E 2.3-16 produced 49 hp (36 kW) and 41 ft·lbf (55 N·m) of torque over the basic single overhead cam 2.3 engine on which it was based. The 2.3 L 16 valve engine made "185 hp (137 kW) at 6,200 rpm and 174 ft·lbf (235 N·m) at 4,500 rpm, the over square 95.50 x 80.25 mm bore and stroke dimensions ensuring that it revs easily up to the 7000 rpm redline". Acceleration from 0-100 km/h (62 mph) was 8.0 seconds, and the top speed was 230 km/h (143 mph)

The roadgoing version of the engine was reconfigured with reduced inlet and exhaust port sizes, different camshaft profiles, no dry sump configuration and Bosch K-jetronic replacing the specialised Kugelfischer fuel injection. These changes helped bring power down to the required 185 bhp specification, but still resulted in a "remarkably flexible engine, with a very flat torque curve and a wide power band". The heads for the engines were cast at Cosworth's Coscast foundry in Worcester and sent to Germany to be fitted to the rest of the engine, some of which were very different from the standard 2.3 including pistons of light pressed alloy and rings designed to withstand higher engine speeds, whilst con-rods, bearings and bearing caps were found to be strong enough as standard and left unaltered.

The 2.5 model
An enlarged 2.5 L engine replaced the 2.3 L in 1988 and increased output by 17 hp (12.5 kW) with a slight increase in torque. For the European market without catalyst the car delivered 202 bhp (150 kW). The catalytic converter was becoming prevalent at this time, and catalyst equipped 2.5-16s produced a slightly reduced 197 bhp. It is a subject of debate whether the 2.5 L engine was developed and built by Mercedes or Cosworth. Mercedes were not keen to broadcast the fact that their most sporting saloon car has an engine developed by a British company. However some cylinder heads from 2.5 L cars are stamped with the Coscast logo indicating they were cast at Cosworth's foundry just like the 2.3s. Cosworth also list a Project code "WAB" for the development of the 2.5-16 cylinder head just as they do for the 2.3-16 cylinder head.

16v Differences
Due to their performance status, the 16 valve cars were in some areas very different from the other 190 models. The body kit on the 2.3 16 and 2.5 16 reduced the drag coefficient to 0.32, one of the lowest cd values on a four door saloon of the time, whilst also reducing lift at speed. The steering ratio was quicker and the steering wheel smaller than that on other 190s, whilst the fuel tank was enlarged from 55 to 70 L.

The getrag 5-speed gearbox was unique to the 16 valve and featured a "GT" gear pattern with 'dog-leg' first gear, left and down from neutral. This meant that the remaining 2nd, 3rd, 4th and 5th gears were in a simple H pattern allowing fast and easy selection. The gear change quality was, however, noted as "notchy, baulky", criticisms also levelled at the E30 BMW M3 which shared the same gearbox. An oil cooler was fitted to ensure efficient oil cooling for the inevitable track use many of these cars were destined for.

The strictly four-seater interior had Recaro sports seats with strong side bolsters for front and rear passengers. 3 extra dials - an oil temperature gauge, stopwatch and voltmeter - were included in the center console. The, 190E 2.3-16 was available in only two colours, Blue-Black metallic, and Smoke Silver (which looks gold). The introduction of the 2.5-16 brought along two extra colours, Almandine Red and Astral Silver. All 2.3-16 valve 190 models are fitted with a Limited Slip Differential (LSD) as standard.

They were also available with Mercedes' ASD system which was standard equipment on the 2.5-16v. The ASD is an electronically controlled, hydraulically locking differential which activates automatically when required. The electronic control allows varied amounts of differential lock from the standard 15% right up to 100%. It is not a traction control system however, and can only maximize traction rather than prevent wheel spin. Activation of the ASD system is indicated by an illuminating amber triangle in the speedometer.

The suspension on 16 valve models is very different to the standard 190 (w201). As well as being lower and stiffer, it has quicker dampers, larger anti-roll bars, harder bushings and hydraulic Self-Levelling Suspension (SLS) on the rear. This allows the rear ride height to remain constant even when the car is fully loaded. At the inauguration of the new, shorter Nürburgring in 1984, a race with identical cars was held, with former and current F1 pilots at the wheel. A rather unknown young driver named Ayrton Senna took First place in that race. Private Teams such as AMG later entered the 2.3-16 in touring cars races, especially the DTM. In the late 1980s, the 2.5-16 (never released in the United States) raced many times, against the similar BMW M3 and even the turbocharged Ford Sierra Cosworth

The Evolution models
Although the Mercedes 190e and Mercedes 190 models were well received the Mercedes Benz 190e 2.3 16 and Mercedes Benz 190e 2.5 16 were the real winners. However, Mercedes needed to fight backWith the debut of the BMW M3 Sport Evolution, Mercedes' direct competitor, it became obvious that the 2.5-16 needed a boost for the circuit. In March 1989, the 190E 2.5-16 Evolution debuted at the Geneva Auto Show. The EvoI, as it came to be called, featured a more aggressive bodykit including a new spoiler and wider wheel arches, although many of the changes were to under-the-skin components such as brakes and suspension as well as a full SLS suspension allowing vehicle ride height to be adjusted from an interior switch. All were intended to allow the Evolution cars to be even more effective round a track.

in terms of performance the EvoI's output was, on paper, identical to the 202 bhp of the "regular" 2.5-16. However this car had a redesigned engine of similar capacity but, most importantly, a shorter stroke and bigger bore which would allow for a higher rev limit and improved top-end power capabilities. Additional changes stretch to "rotating masses lightened, lubrication improved and cam timing altered".

Only 502 units of the Evolution model were produced for homologation in compliance with DTM rules. For those customers desiring even more performance an option PowerPack option engineered by AMGwas available for merely DM18,000. The PowerPack option included hotter camshafts, a larger diameter throttle body, more aggressive ignition and fuel management as well as optimization of the intake and exhaust systems. The net result was an additional 30 bhp. While the Evolution I model did quite well, engineers knew that the 190E could be improved further. In March 1990, again at the Geneva Auto Show, the 190E 2.5-16 Evolution II was shown. With the success of the first Evolution model, this model's 502-unit production was already sold before it was unveiled. This car retailed in 1990 for$80,000.

The "Evo II" included the AMG PowerPack fitted to the same short stroke 2.5 engine as the Evolution, as well as a full SLS suspension allowing vehicle ride height to be adjusted from an interior switch. Again the most obvious modification to the Evolution II is a radically designed body kit designed by Prof. Richard Eppler from the University of Stuttgart, with a very large adjustable rear wing, rear window spoiler, and unique Evolution II 17 inch wheels. That body kit served an aerodynamic purpose — it was wind tunnel tested to reduce drag to 0.29 while at the same time increasing downforce. Period anecdotes tell of a BMW executive who was quoted as saying "if that rear wing works, we'll have to redesign our wind tunnel.". The anecdote claims that BMW did.

The 16v AMG Power pack
Fitted as standard to the Evolution II models, and optional on Evolution models, the AMG Power Pack increased power to 232 bhp (171 kW) at 7,200 rpm and torque to 181 lbft at 5,000 rpm, whilst pushing the top speed up to 155 mph. In their final incarnations, these engines produced up to 420 bhp in racing tune.

The Evolution models and all other 190 with 16 valves get supported by the Mercedes 190 Owners Club. Further information can be found on www.mercedes190.co.uk.

AMG Models
At the time of the 190's production, AMG was not a part of Mercedes-Benz, but a separate tuning company in its own right. Therefore there are no 'official' AMG versions of the 190E in the same vein as today's AMG cars. AMG did produce a number of 190Es with their own 3.2 development of the straight-six engine, producing approximately 220 bhp.

The History Of The 190e 16v Model: There was a time when cars were designed out of a passion for motor sports; one of these cars is the Mercedes Benz 190e 16v. To understand the uniqueness of this automobile we must return the late 70's when planners were conceiving the 190 class and its top model, the 16V. Mercedes thought rallying was the best arena to showcase their new model line, but this plan quickly changed to road racing. As a result, Mercedes strongly desired to promote the new model’s attributes and showcase its’ abilities in motor sports.

Contributing to the fantastic driving dynamics is the now famous multilink rear suspension. It was first released on the 190 series and was instrumental in providing sporty and competitive handling. Mercedes also collaborated with engine building masters, Cosworth Technology Ltd. to help develop the 16 valve cylinder head with mechanical valve lifters. They came up with 185bhp from 2.3 litres and 204bhp from the 2.5 model which may not sound like a lot (compared to today’s engines) but don’t forget this was 1983 (almost 20 years ago) and the car was lightweight compared to today’s heavy weights.

In the summer of 1983, the 190E 2.3 16V set out to break as many long distance high speed FIA records as possible at Nardo, Italy. After 202 hours of continuous running, multiple records were broken including the 50,000 km level at an average speed of 248 kph (154mph). Very impressive when you consider they had to stop to refuel, change drivers and service the car while the clock was ticking. During these endurance trials there were some minor aerodynamic modifications including removal of the mirrors and wipers. In addition, a lower rear axle ratio permitted a higher top speed but overall this car was almost stock and reflected well on the entire 190 series.

May 84 was a monumental time for the 16V. The new Nurburgring racetrack was hosting its first F1 race and a 16V won the supporting race. All the cars were 16V’s driven by many former world champions. Moss, Lauda, and Hill were all beaten by a young upstart driver named Senna.

The DTM race series became popular around this time so Mercedes entered multiple cars after satisfying the rules stipulation that required 5,000 road going versions to be built. BMW entered DTM with its enthralling M3, which was a direct rival to the 190. Competition forced Mercedes Benz to enlarge engine capacity to 2.5 liters and eventually release a more advanced Evolution 1 and 2 versions with more aerodynamic aids and horsepower. At this point, the famous engine tuner, AMG, was called upon to create a team of their own. Mercedes and AMG went on to win over 50 DTM races and numerous titles, which solidified their dedication to motor sports, which lives on to this day.

Since Mercedes created the car for racing it has features like a Getrag gearbox with dogleg first. The pneumatic rear suspension keeps the tires in contact with the road. An aerodynamic package was fitted, which consisted of a front spoiler, wheel arches, side skirts, rear valance and rear wing.

ABS brakes are standard as well as brake cooling ducts to keep brake temperatures under control. Black leather covers the incredibly comfortable electric sports seats. Mercedes Benz had added a stopwatch, voltmeter and oil temp gauge to the lower center console backing up its motor sports intentions. In the rear, there are only two Recaro seats with supportive side bolsters, which makes this a 4-passenger vehicle only.

source: http://www.markthomastrimming.com/storage/merc/history.htm

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