Mercedes-Benz W201 190E 2.5-16 Evolution II

In 1982 Mercedes-Benz released the production version of more than a decade's research into developing a compact format, efficient and safe luxury car. The name '190' referred back to the 1950 and 60s versions of 'reduced power output' models of their mainstream saloon car range. The 190E specified a fuel-injected 2.0 litre, four cylinder engine, whilst a 190 model, without the 'E' (for einspritz' appellation, referred to the same engine, but using a carburetor.

 

This is the version most commonly seen in taxis, along with a 2.0 litre 4-cylinder diesel, with even less power......

 

Then something strange happened within the halls of Mercedes-Benz....

 

190E 2.3-16 & 2.5-16 "Cosworth":

 

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 190 E rallying, and asked British engineering company Cosworth to develop an engine with 320 bhp (239 kW) 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, making the 2.3-16v appear outclassed. With a continued desire to compete in high-profile motor sport with the 190, and also now an engine to do it with, Mercedes turned to the Deutsche Tourenwagen Meisterschaft (DTM) (German Touring Car Championship) motor sport 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 190 E 2.3-16, and debuted at the Frankfurt Auto Show in September 1983, after its reputation had already been established. Three cars, only slightly cosmetically altered, had set three world records in August at the Nardo testing facility in Italy, recording a combined average speed of 154.06 mph (247.94 km/h) over the 50,000 km endurance test, and establishing twelve international endurance records. The Mercedes 190-E Cosworth was also featured on the second episode in series fifteen of the popular car show Top Gear.

 

Engin:

 

2.5-16 Cosworth

The Cosworth engine was based on the M102 four cylinder 2.3-litre 8-valve 136 hp (101 kW) unit already fitted to the 190- and E-Class series. Cosworth developed the cylinder head, "applying knowledge we've learnt from the DFV 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 2.3 L 16-valve engine made "185 hp (138 kW) at 6,200 rpm and 174 lb·ft (236 N·m) at 4,500 rpm. The oversquare 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 less than eight seconds, and the top speed was 230 km/h (143 mph).

 

US-Specification cars had a slightly reduced compression ratio (9.7:1 instead of 10.5:1), and were rated at 167 hp (125 kW) @ 5800 rpm and 162 lb·ft (220 N·m) @ 4750.

 

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 (138 kW) 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, parts of which were different from the standard 2.3 including light pressed alloy pistons, 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.

 

16v differences:

 

Due to their performance, the 16-valve cars were 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 manual gearbox was unique to the 16-valve and featured a 'racing' 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 gearchange quality was, however, noted as "notchy, baulky", criticisms which weren't levelled at the BMW M3 (E30) which shared the same gearbox. The pattern is also unusual in that the driver engages reverse by shifting left and up from neutral, as for first gear in a conventional pattern. This was demonstrated in a Top Gear episode (S15E02) where James May took a 190E 2.3-16 Cosworth and repeatedly confused reverse and first gear. An oil cooler was fitted to ensure sufficient 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 centre console. The 190 E 2.3-16 was available in only two colours, Blue-Black metallic (Pearl Black in the US), and Smoke Silver. The 2.5-16 added 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 from 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 then unknown Ayrton Senna took first place.

 

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 RS Cosworth.

 

Evolution models:

 

2.5-16 Evolution II

With 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 190 E 2.5-16 Evolution debuted at the Geneva Auto Show. The Evo I, as it came to be called, had a new spoiler and wider wheel arches. Many changes were made to under-the-skin components such as brakes and suspension. There was 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.

 

The Evo I's output is similar to the 202 bhp (151 kW) 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". Cosworth also list a project code "WAC" for the development of the short-stroke Evolution engine.

 

Only 502 units of the Evolution model were produced for homologation in compliance with DTM rules. For those customers desiring even more performance, a PowerPack option engineered by AMG was available for DM 18,000. 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 (22 kW).

 

In March 1990, at the Geneva Auto Show, the 190 E 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.

 

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. An obvious modification to the Evolution II is a radical body kit (designed by Prof. Richard Eppler from the University of Stuttgart) with a large adjustable rear wing, rear window spoiler, and Evolution II 17-inch wheels. The 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.

 

As mentioned 500 were made in "blauschwarz" blue/black metallic. But the last two, numbers 501 and 502 were made in astral silver.

 

[Test taken from Wikipedia]

 

This Lego miniland-scale 190E 2.5-16 Evolution II sedan has been created for Flickr LUGNuts' 84th Build Challenge, our 7th birthday, - "LUGNuts Turns 7…or 49 in Dog Years", - where all the previous challenges are available to build to. In this case Challenge 57, - "From Mild to Wild", for vehicles that have been turned into something special out of the ordinary. And also challenge 33, - "Size Matters", - as a buddy challenge with Sirmanperson, who has produced the same 190E 2.5-16 Evolution II in 1:17 scale.

Done