The German stars meet their stiffest test yet as Sierra RS Cosworth takes on the BMW M3 and Mercedes 190E 2.3-16. So who tops the league now? – Autocar
By ditching the original Sierra Cosworth’s jumbo jet rear wing for its newest and possibly greatest RS, Ford has struck a blow against the boy racer it will surely never regret. Where that wing was all about racing, raw performance and track ride and handling, the new model’s discreet spoiler tells a different story – one that sums up Ford’s fastest-ever production car. With its sober three-box body, subtle body add-ons and quietly purposeful air, the Sierra RS Cosworth gains a respectability that sees it in the forefront of high performance sports saloons. Its hariy-chested one-off image has been discarded along with that giant wing.
The change is reflected inside and underneath, with a package of revisions that confirm this boy racer special has indeed grown up. The RS is now a softer, quieter, easier car, with plenty of luxury equipment on one hand and, crucially, no loss of performance on the other. It’s a mixture – on sale now at £19,000 – that meets BMW’s M3 and Mercedes-Benz’s 190E 2.3-16 head on.
In this battle the production Sierra RS takes the middle ground. On its left, the M3 is a pure homologation special – a roadgoing version of a racing car, just like the previous Sierra RS, and to many people, immediately appealing because of it. On its right, the 2.3-16 has always been a full production car, albeit made in limited numbers. The motorsport connection is confined to specialist help and manufacture of the cylinder head. Like Ford, Mercedes uses Cosworth.
Ford is a clever company and the timing and execution of the new Sierra RS show just how clever. It has managed to combine the appeal of the successful homologation special – 1987 world touring car champion and victor of 29 international rallies – with a production capability of up to 7000 cars a year at time when, massive rear wing or not, everyone knows this Ford is the car to beat. That it has done so without skimping on redevelopment shows an understanding of the sports saloon market worthy of either its German rivals. The icing on the cake is that it has done so at a price that greatly undercuts those rivals.
Together, then, are three cars which, different backgrounds apart, set out to do the same job on remarkably similar ingredients. In choosing the four-door Sapphire body – surely as much for the extra bodyshell rigidity as any styling statement – the Ford joins the Mercedes in offering the most traditional looking package. The Mercedes has the longer wheelbase but dimensions elsewhere are within an inch or two of each other, although the Ford’s claimed kerb weight is a healthy 200lb less.
The BMW M3 is smaller everywhere than its rivals. It is a good 4ins less in the wheelbase than the Mercedes and has only two doors in its unique M3 body which sees a greater rake to the rear window, making the car look less upright than standard 3-series models. ‘Sportification’ of these otherwise commonplace mid-range family cars follows a familiar pattern of deep front spoiler, sill extensions and small wing on the bootlid, plus of course blacked-out chrome trim. The BMW sparkles hardly at all, especially when, like the test car, the body and interior are in unrelieved black.
All the engines are water-cooled fours with cast iron blocks. Their performance credentials all lie in alloy head: twin overhead camshafts and four valves per cylinder are common, as are sophisticated electric fuel and ignition systems. The BMW and Mercedes share a 10.5 compression ratio, with power from their 2.3litre engine ranging from 185bhp for the Merc to 200 for the M3, developed at a heady 6200 and 6750rpm respectively. No shortage of power here, even if the lack of either bulk cubie capacity or forced induction does result in torque around the 175lb ft mark.
The Sierra claims 205lb ft of torque and Ford says 80 percent of it is available between 2300 and 6500rpm. On paper this is the Sierra’s greatest advantage over its rivals; with 204bhp, it is not very far ahead of the BMW on power, though the peak does occur lower at 6000rpm. The engine is a 2-litre with the same outline specification as the others but topped by a Garret AiResearch turbocharger blowing at a maximum of 0.7bar.
Close ratio gearboxes are used throughout, those in the German cars with dogleg first gears and direct drive top, while the Sierra has a conventional gearchange gate and 0.8 fifth ratio. With a 3.64 to one final drive there’s nothing overdrive about it, though, and maximum speed occurs a little past the power peak. The engine would need to pull 6500rpm in order to record a true 150mph, which our test car couldn’t manage on what was a very windy day at Millbrook.
The Ford and the BMW share the same basic suspension of front struts and rear semi-trailing arms, the Mercedes using its own multi-link independent rear end. Front and rear anti-roll bars are common to the three cars, as are 7ins rims shod with 15ins 205 section tyres. The German cars make do with 55 profile boots (Goodyear NCTs on the M3, Pirelli P6 on the Mercedes) while the Ford uses 50 profile Dunlop D40s – with surprising results.
Big boosted disc, all with standard anti-locking, are fitted and steering is power assisted rack and pinion (BMW and Ford) and recirculating ball (Mercedes). Equipment runs the gamut of luxury car fare with no obvious omissions, even if the 190’s manually adjustable driver’s mirror strikes a peculiar note in so expensive a car. Four-wheel drive isn’t available for any of these cars yet, but it seems logical move. As revealed in Autocar 13 January ‘87, Ford’s four-wheel drive Sierra RS Cosworth is closest to production.
Behind the Wheel
Compared with the classy black leather interiors of Mercedes and BMW, the Ford’s cabin comes across as a bit of a boudoir, with its pastel shades and obviously synthetic trim, dominated by a cumbersome dashboard of heavy-handed design and obvious plastic. The recaro seats and RS leather-bound steering wheel and gear knob cannot disguise the truth of this cabin: you are in mid-range Ford saloon, nothing more. The good news is that the driving position is easily the best of the bunch if you’re 6ft or more (anything less than that and the BMW is just as good) and the seats, too, are the best. These score most points over the others for lateral support which extends up to the shoulder blades, even if their height does make sitting in the back a little claustrophobic. Add the best ergonomics of the group, well-placed pedals and gear lever and clearly laid out instruments and the Ford is quickly comfortable and undemanding. If only it had class.
Our test M3 was converted to right-hand drive by Birds at a cost of £4440, to make a total without options of £27,420. With BMW UK’s allocation of 100 left-hand drive only M3s now all sold, this is the only way to buy a new M3 in this country. Or appearance it would be impossible to pick it from a production line right-hooker, with not a mismatched panel or creak anywhere.
The heavily bolstered, leather-trimmed seats are superb, providing lots of well-placed support but against the Ford, not the same rock steady location. Nor is there the same amount of room. Fore and aft travel is restricted and the cabin always feels narrow, making the driving position far less accommodating than either the Ford’s or the Mercedes’. Drivers of below average height will fit like a glove, however. Complaints then are few, there’s the overwhelming blackness of everything relieved only by little flashes of blue on the scattered M badges, and a centre console with a switch layout that’s illogical and fiddly. Against this, as always in BMW, the instruments are a model of clarity. Plus there’s something about this car, a slightly wicked totally indulgent side, that guarantees a smile everytime you snuggle down into it.
The Mercedes at £27,300 plus options doesn’t quite manage that, but its’ close. Here is another delicious cabin that’s put together as well if no better than the BMW’s (the sound of the Mercedes doors closing is that of a precision instrument) but rather more “user friendly” with its curvaceous instrument panel and grey houndstooth trim for headlining and seat and door inserts. It’s warmer than the BMW but not sickly like the Ford.
The instruments are not as simply marked as the BMW and, compared with the Ford, the switch gear’s locations and design is poor – an area where the 190 is showing its age rather quickly. The driving position is a curious and overall rather disappointing mixture. On the one hand there is an amount on fore and aft travel for the seats which wouldn’t shame an S-class – a seven footer could drive this car – but on the other there is a typically large and very low set steering wheel that makes anything other than a straight legs, straight arms driving position an awkward compromise. The position isn’t saved by the seats: compared with the other they offer only token sideways support.
None of the cars is guilty of causing aches however, for all the front seats have fine lumbar support. The Mercedes are equipped with the best shaped back seats but the least room in which an adult can enjoy them. Lacking headroom and leg room makes the BMW impossibly cramped, while in the Mercedes a compromise can be struck that at least allows one big adult to ride in the back behind the passenger seat. With adequate legroom, excellent rear headroom and superbly sculpted rear backrests this is in fact a fine place to sit. The Ford has by far the most cabin room, though comfort in the rear is let down by a poorly shaped backrest. With a 60-40 split fold-down seat opening on to an already good sized boot, it’s again the Ford that scores highest for carrying luggage.
Performance, Economy
The Ford’s engine is neither mechanically quiet nor vibrations free, but let there be no doubt that it is the master of this group. There’s more power throughout the range, spoiled neither by turbo lag or lack of low down response and it is willing and able, time after time, to record acceleration figures that embarrass its German rivals.
Dropping the clutch at 4800rpm in the dry sees the car rocket to 60mph in 5.8secs. There’s never a suggestion of the engine bogging down, something that’s quickly appreciated around town. Second will pull away from a stop and trundling in third or fourth at very low revs is never a concern. This flexibility, surprising for a 2litre turbo, is matched by an even power flow that builds progressively into the car’s greatest performance strength; its potent mid range.
From 4000rpm there’s a wall of power to 6000. Tap into this band in third gear and overtaking become effortless, while even left in fifth there’s sufficient kick to knock you back in the seat when you press the accelerator hard at 110mph. The top speed is disappearing in view of Ford’s 150mph claim – on a less windy day there would be a little more – but in other ways this is benchmark performance for a sports saloon of any price.
In contrast, the second quickest of the group, the BMW M3, feels a little like a castrated racer. All the ingredients are there – the high torque and power peaks, the good response and businesslike sounds – only there’s 100bhp missing.
With a snatch-free drivetrain and tractability from walking pace, coupled with a 6750rpm power peak and 7500rpm red line, there’s a mighty broad engine band in which nothing much seems to happen. In practice a lot is happening; any car which gets to 60 in 6.5secs; the Test Results figure of 7.1 is for an early test car on a wet track is not short of performance. And indeed the BMW’s stride is a deceptive one.
Compared with a small BMW six, this engine is rough and noisy. Nor does it rev to its high maximum with the alacrity one expects, so that by most sports saloon standards performance is brisk if rather bland. To this tune there’s nothing cammy about the power delivery, just a long, even surge to the red line, without the Ford’s mid-range punch or top end kick. It’s possible the right hand drive conversion, which requires a new exhaust manifold, doesn’t help the little Bimmer in the area of performance and power delivery.
Apart from a terrific top speed, the Mercedes’ performance must be seen these days to be no more than average for this sort of car at Mercedes’ sort of price. A full 2secs slower to 60 than the Ford, the engine also lacks the Ford’s strong mid-range but has a more clearly defined power band at the top than the BMW. For this latest acquaintanceship with the 2.3-16 we used an automatic version. Gear changes are as efficient as with any Mercedes automatic but the change-up points are hardly in keeping with so sporty a car, and this needlessly highlights the engine’s power characteristics. With the accelerator flat to the floor gearchanges flow through at the 7000rpm red line, but in everyday driving the car often appears to be in a gear too high for ideally quick response.
Without an eager part-throttle kickdown the accelerator pedal must be pushed past its stiff detent for action stations. The box will go back to third or second, taking the engine well into its power (and noise) band, but it’s an uneven way to travel that doesn’t do justice to the Cosworth-developed engine: it is smoother and more flexible that this automatic would have you believe. Unfortunately we also know from experience that the manual gearbox has a notchy change not up to either the Ford’s or BMW’s. This, and overall performance, will have to improve with the forthcoming 2.5litre to keep abreast of the competition and retain the Mercedes’ reputation for smoothness.
Not surprisingly, where the Merc automatic does score is fuel economy. Running the cars in convoy for 600miles resulted in an overall figure of 21.4mpg for the 190 (against the manual test car’s overall 23.5), and this is enough to pip both the BMW (20.9) and Ford (18.7). Of the three, the most worrying is the Ford’s thirst. After a session at Castle Combe racetrack it recorded 13.7mpg, against the BMW’s 16 and the Mercedes’ 14.6. During performance testing it dropped to 11.6. It all goes to show that while, like the others, the mid 20s are possible on a gentle run, use all the turbo’s performance and fuel consumption is extravagant.
Handling
The driving sleet that lashed Castle Combe on the day of our visit was no bad thing. If these cars had vices, they would show them.
The most secure car here, but also the slowest, was the Mercedes. Left in third gear on the delicious selector lever, it could be hustled through the sleet with perfect poise, mildly understeering through the apexes but rarely missing them, and never seriously stepping out of line.
Despite that big, low-set steering wheel with its far from quick 3.2 power assisted runs lock to lock, the car could be thrown into corners with impunity, displaying a neutrality on or off the throttle that resulted not just in neat lines but the most relaxing drive of the day. The body rolls more than the others – something highlighted by the seats’ lack of support – but the damping its first rate and stability at speed or under heavy braking superb. This is a viceless car.
On the road it shows. Grip, turn-in response and feel through the steering are all of a high order, with reserves of stability to take the sting out of the most treacherous road or over ambitious driver. In spirited driving the only attitude is that mild understeer and body roll. You can dial in oversteer if you want – although the steering doesn’t encourage it – but it’s difficult to think of a circumstance where any tail-happiness would intrude unwanted, or unexpected. The result of all this is a car with less than razor sharp reflexes – much more grand touring than sports car – but of elevated ability.
The two other cars are much sharper in their behaviour and much more rewarding to press-on driver with their flatter cornering and more uncompromising natures. Having said that, there are key difference between Sierra and M3 that separate them utterly.
These grouses aside, the car is marvellous. It has things that BMW and Mercedes seem to have forgotten about: decently quick steering, a firm and positive gear shaft, a firm and reassuring brake pedal and tyres – ultra low 50 profile, remember – that offer grip the other two cars can only approximate. Add the best driving position and most grippy seats of the trio, plus all that fast-acting turbo power, and you have a recipe for the performance and ability that make the Cosworth a real driver’s car.
We were still filled with trepidation when we took to the track, the sleet having given way to hail. Surely here was a recipe for a driver’s car, yes, but also one enormous handful. The reality was different. After only a few laps of mixing 200bhp with hailstones through 100mph corners we had our answer. The car is forgiving, almost gentle, well balanced and surefooted to the point that it is instantly quicker than the others, even in the hand of a driver inexperience with Castle Combe’s sweeping bends. With that wonderful brake deal unleashing such potent force – the best brakes of the group by a considerable margin – and traction out of corners good enough for the mid-range power to go down hard, the car quickly falls into a rhythm of going deeper and powering out sooner. And slight oversteer on the exit is easily corrected by tug on the steering wheel.
Inherent balance aside, the thing that makes the Cosworth stand tall is its controllability, and so it is on the road. The variable ratio steering which offer such precision and poise on the track gives the car and agility missing in others, even if there is sacrifice to be made in road feel. Not everything translates well to the road, though. Where on the track the gearchange had been firm and positive, in everyday driving it emerges as distinctly truck-like and hard work with heavy, long throws and a good deal of notchiness.
The BMW’s lap time of Castle Combe, 3sec adrift of the Cosworth’s, isn’t all to do with the Ford’s superior mid-range punch and wet traction. It’s as much to do with the BMW’s grip and handling, its steering, different pedal weights and gearchange. Of the three it’s the one that demand respect in the wet, and of all three it’s the only one that will seriously bite back if pushed too far. This then, is the most difficult car to drive of the ground and the pity is that even when mastered it’s a whole 3secs slower than the Ford – and not nearly as tidy and reassuring.
The problem starts with the steering. It’s too light, vague around the straight ahead and, with four turns lock to lock, too low geared to capitalist on the agility the car’s compact dimensions should give it. It has the best feel of the group but on its own this is not enough.
The pedals, with their different weights and degrees of travel, are also more hindtrance that help. The spongy brake pedal, despite a strong and progressive braking force, is hugely disappointing on the track. Likewise, the gearchange: the racing pattern is in keeping, but the lever’s over-light and vague travel certainly is not. These aspects, in league with what is a cramped driving position you’re tall, fail to give the M3 the ‘in control’ feel the Ford so impresses on the driver. A shame, because in this car you need to be in control.
Once used to the large steering inputs, turn-in quick and accurate. Under power the M3 understeers – more than either of the others. Get off the power at the wrong moment and the car oversteers briskly, again much more so than even the Ford, though it is made more dramatic than it need be by that steering. Where in the Cosworth a quick tug will correct a slide early and precisely, an out-of-shape M3 requires armfuls of lock, the car fishtailing wildy unless correction has been judged well. In the wet there’s power-induced oversteer, too; at Castle Combe we noticed this most coming out of corners, where it was never possible to get down as much power as the Ford would have thrived on.
On the road in the dry the M3 grips, no question about it. Of the three it has by far the firmest suspension settings, best damping control and flattest body. There’s an on-rails cornering feel here that’s missing in the others. The gearchange fares better, too: it’s still a luxury car gearchange rather than a sportster’s, but it can be stroked between ratios with one finger for a far more sophisticated feel than the Ford’s. High speed stability, even on gusty motorways, is excellent, as is straight stability under heavy braking – both areas well up on the Ford, and probably the Merc too.
Ride and Refinement
The BMW’s stiff suspension and iron damping and body control give it the firmest ride of the group, and also the noisiest. Bumpthump and tyre roar intrude at most speeds. Around lumpy city streets comfort suffers but for touring there’s nothing objectionable about the ride for this sort of car. It jiggles quite sharply on sudden bumps and bang hard over potholes, whatever the speed, but it’s a small price to pay for such tautness. The Mercedes, likewise, jiggles and jolts a fair bit, and lets plenty of tyre roar into the cabin. But it’s not as unyielding around town and has a more supple ride over indifferent surfaces taken at speed. Shame about the noise though.
The Cosworth Sierra scores heavily for its isolation of road and tyre noise – it really is good. Ride, too, is very acceptable: it’s the softest around town and the least susceptible to jiggling over small frequently bumps. The penalty here, as mentioned, is a degree of bounce – a slight suggestion of underdamping. For this we mark it just behind the Mercedes on overall ability, though for short journeys on bad roads, rather than a leisurely fling to St Tropez and back, there’s no denying the Ford’s comfort advantage.
Big capacity fours like these are not noted for inherent smoothness and none of these engines changes that. All suffer from vibration – the Ford is the worst, closely followed by the BMW – and all have intrusively noisy top ends of dubious character. The Ford’s note is the gruffest, especially low down where it’s joined by some gear whine, while the Mercedes, overall the quietest car of the group, has an equally purposeful but more refined note. We expected music from the BMW’s engine, but it never appeared. What you get is an uncharacteristic sound far from the silky smoothness and high rev bark of a small BMW six. All the engine are dominant enough, with the varying amounts of road roar, to mask wind noise, which is not a problem in any of the cars until past 100mph.
Conclusions
There are all fine cars, as purposeful and capable as any to have the label sports saloon. Office opinion as to a winner is divided, which is why we have taken the opportunity to include the personal views of those involved in the test.
The facts, though, are these: the BMW is cramped and fails to give drivers the sort of easy controllability they deserve, especially in view of less than forgiving ultimate handling. It looks the part, is well built and recks of class.
Likewise the Mercedes. There’s an aura here you don’t get in the Ford, an integrity and quality throughout its being. It’s less cramped than the BMW, softer riding and much quieter but with performance that has lost its edge by today’s standards and a driving position that won’t suit all.
And the Ford is, well, in some disappointing ways, just a Ford. That is not to say it is not well built or well equipped – it is. But there can be no denying the ordinariness of the car in some areas. It still looks like a rep’s car and has a cabin design uninspirational in the extreme. More serious is the flawed high speed stability and the car’s thirst.
Against this is a range of attributes that make the Sierra RS Cosworth the best car of the group. With the best performance, driving position, seats, brakes, ergonomics, steering and grip, plus sportily failsafe handling and the least road noise of the bunch, it could not be any other way. Plus it seats four adults in a way the others cannot and costs upwards of £4000 less. The best sports saloon in the business is British.
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July 27, 2009
1986 - 1989, Articles