BMW’s hot M3 takes off as M-B’s 2.3-16 fades away – Automobile
What we have here is a story about a beginning and an ending. Think in terms of yin and yang, birth and death, the very rhythms of the cosmos. Think about the passing of a grand baton.
Or just think about exactly what’s happening. An exciting new automobile is bursting on the scene, at the very moment the car that would have been its direct competitor is beating an undignified retread.
The racy little M3 from BMW and Mercedes’ 190E 2.3-16 share a basic recipe: hot sixteen-valve four-cylinder stuffed into their makers’ smallest sedan bodies, along with extra-firm suspensions and fast-looking aero add-ons. Both keep one eye on European Group A Touring Car racing, the other on monied enthusiasts who are powerless to resist a personal hot rod from a German factory.
Yet these two cars come across as very different animals. We now know they differ widely in terms of success on the road (we loved the sporty Mercedes, until we drove it back to back with the M3), and apparently they’ll differ in success on the market, too: Mercedes-Benz of North America has unceremoniously dumped the 2.3-16 from its 1988 lineup.
Perhaps we shouldn’t be too surprised by these divergent fortunes. Even though Bayerische Motoren Werke and Daimler-Benz drew a bead on the same target with these high-powered missiles, they were aiming from two quite different positions. Traditionally, Mercedes cars have been stout and solid, competent to a fault, almost weighed down by their own quality and excellence. Powerful engines moved them, taut suspensions kept them in control, and firm seats propped up their occupants.
By contrast, BMWs have always had a sporting flair. Smaller, lighter, more lithe, and more maneuverable, they played the wide receivers to Mercedes’ power backs, the attack subs to D-B’s boomers.
Is it any wonder, then, that Munich could step up to a race-based sports sedan more deftly than Sindelfingen could pare down to one? At the very least, dealer salespeople in BMW’s American showrooms could speak the sporting tongue more convincingly than their counterparts at the Mercedes stores. So today we have a genuine, 192bhp BMW street racer sure to be in hot demand, and a Mercedes “equivalent” we can only remember (or go drive in Europe, where it remains for sale).
The M3 has clearly focused commitment to the fast-paced life. Mechanically, it blends some serious high-speed hardware with the solid 3-series base. And it comes out better – faster, to be sure, but also more responsive, better balanced, maybe even safer – than any of its 325 siblings. At $34,000, it is the most expensive of the Three family, but, remember, the 190E 2.3-16 sold (when it sold at all) for $41,150. The M3 may be the best product BMW offers in this country, especially if we give it points for continuing the marque’s tradition of appealing to the sporting spirit.
Little in this world tickles such a spirit like lots of sheer power. The 2.3litre engine was developed by Motorsport GmbH – BMW’s high-output, high-profile subsidiary, and the “M” in all those exciting cars. It spins out 192 horsepower at a lusty 6750rpm, and is almost in the modern motorcycle class for technology and tuning. If you’re a fan of specific output, and of what that tells you about state of tune, here’s about as close as you’ll get to 100bhp per litre without turbochanging. The M3 develops 83.5bhp per litre. A 3.2 Ferrari makes slightly over 81; an MR2, 70; a Corvette, under 43.
The iron-block engine uses Siamesed cylinder bores to make room for big 93.4mm holes: the short stroke of only 84.0mm helps the innards to spin past 7000rpm without trauma. Cast pistons are designed to trim weight, and they carry the wrist pin high to permit a longer connecting rod; this reduces rod angularity in changing reciprocating motion to rotation.
Double chain-driven camshafts ride in the aluminum cylinder head and operate the light 32mm and 37mm valves directly through shim-adjusted bucket tappets. Centrally located spark plugs and squish areas around the perimeters of the shallow pent-roof combustion chambers give enough turbulence and sufficiently short flame travel so that compression ratio can be all of 10.5:1, Bosch DME (Digital Motor Electronics) controls the ignition and the fuel injection. On one side of the head is a beautiful bank of four alloy intake runners, each with an individual throttle butterfly. On the other is a tubular four-into-two exhaust header.
The torque peak of 170 pounds feet comes at a high 4750rpm, further evidence of how tightly wrapped this semi-racing engine is. A five-speed gearbox with ratios that feel unusually close-spaced and short overall helps the engine run where it does its best work. In crafting the car for the US market, BMW changed its shift pattern from the European sport configuration, with first outside the H, to the arrangement more familiar here, with fifth outside the H.
While sorting out the suspension so it could handle the new speed and power, BMW’s engineers came up with a specification that brings new-found stability and dependability to the 3-Series platform. True, ride height is awfully low, and spring and damper rates are quite high. But ramp clearance and ride harshness are not affected adversely enough to make us want to give up any of the M3’s fine, firm control.
Front suspension geometry incorporates much more caster to give greater directional stability. Coil-spring rates are progressive in back but remain linear in front – simply because that’s what worked best. Low pressure gas-charged shocks are incorporated in the struts in front and mounted atop the semi-trailing arms in back. The shocks fight fluid aeration and its attendant heat fade, and provide degressive damping, to give way on extreme impacts and smooth out the ride.
Ambient air gives way, too, more readily for the M3’s passing than for any other 3-series, and by quite a margin. Front and rear aprons with integral bumpers, gently contoured fenders, rocker panel skirts, and a raised rear deck with a wild, angular wing all slash drag coefficient from a 325’s 0.37 way down to 0.33 – and that’s with fattish 205/55VR-15tires.
The rear-end treatment includes a fibreglass cover for the C-pillars that changes the roofline subtly, reangles the backlight, and blends into the higher, flattened trunk lid. That wing is a sturdy slab constructed with polyurethane over a paper honeycomb core. Quality, fit, and match of the new pieces are flawless throughout; our only complaint centers on a spot where the rounded lower edge of the new deck lid wraps over the squared shape at the upper rear corner of the sheetmetal.
Frankly, we`re also not sure whether the wing treatment isn`t going a little far for a road car. It struck us as awfully boy-racerish, with that thing jutting up back there. On the other hand, the rest of the car is unobtrusive and conservative in the normal BMW way, and in any case, this look will shortly come to be widely recognized as simply the M3 style – giving it positive impact in the important circles, whether it`s aesthetically perfect or not.
We may have felt more obvious on the street than we usually prefer, but the M3 left us with little else to complain about. Our time in the car began with a 600mile waltz across New York State and southern Ontario, returning to Ann Arbor from the press introduction at lovely Lime Rock Park in Connecticut. Such a freeway run – particularly in that part of the continent, where the climate is hard on pavement – should show the sport-tuned M3 at its worst. Well, if that`s as bad as it gets, we`ll take it. Yes, the car is a bit stiff-legged when hitting patches and seams at speed, but it`s not too bad. Yes, its engine note is a trifle more prominent than you might prefer, but it`s not too bad. Yes, engine and road vibration conspire to fuzz images in the rear-view mirror, but it`s not too bad.
In short, the comfort compromises the M3 makes strike us as minor and reasonable. For a car of its type, delivering what it does in the way of performance, it doesn`t really demand too much of the long-haul driver. For instance, the engine growl is obvious, but not offensive, even though it`s exacerbated by the shortish gearing (70mph takes over 3600rpm). Those excellent sport seats BMW uses in several of its zestier models contribute a lot, even on the Interstate. Never mind (for the moment) their aggressive side bolstering; they are perfectly shaped on the bottom as well. And the height adjustment helps place them in the car exactly the way you want them.
You`ll also appreciate the M3`s great seating – plus its zippy response and sharp maneuverability – around town and in the busy suburbs. You might notice the small numb spot in the steering right around center – pretty typical of most recent BMW`s we`ve driven but you`ll also realize that the shifter and the pedals are ideally placed, and that they work so sweetly you barely pay attention to them. Instead, you drive the car.
Of course, absolutely the best place to do that is out on the lightly populated back roads, preferably twisty, playful ones. Here, the M3 truly hits its favoured stride. Also, here, it most clearly demonstrates its superiority over Mercedes` similar but different 190E 2.3-16. The M3 is a focused, balanced, effective spots sedan; in comparison, the 190 feels a little unsure of itself, a little confused.
Both cars are comfortable, beautifully outfitted, and swift. But where the Mercedes feels soft, undertired, and resolved to plow at the nose no matter what, the BMW turns in much more crisply, gets more out of its rear tires during cornering, and is more responsive to the driver`s midturn wishes. It, too, is a basic understeerer, but much less determinedly so. Its somewhat more neutral balance allows so attentive driver to obtain attitude changes (generally minor and manageable) using throttle in the bends. A quick lift lightens the tail and tightens the front; go hard back into the gas (especially over 5000rpm), and you get a nice neutral drive out of fast turns, or a little gentle oversteer if the corner is slower and tighter.
Start working both cars hard like this, and you`ll notice a couple of other points the BMW scores. The Mercedes`stubby gear lever has light and lovely action, but it requires far too precise a hand – and too much attention when you`re working hard – to slot into the gates correctly. The BMW`s lever travels farther through a typical gearchange, but it goes where you want it without calling extra attention to itself. Also, the M3`s big tachometer is much more legible, its high-bolstered seats hold more snugly, and it communicates a clearer sense of what`s happening down at the tires.
Both of these sixteen-valve 2.3s are highly tuned, modest-displacement engines, both quite peaky by normal standards. They each have a little performance bubble just over 4000rpm as they climb up onto the torque peak. The BMW`s four seems to hold up a bit better off the peak, while the 190 falls off the cam into a torque pit more readily.
Looking at the torque curves for the engines confirms that impression. Althought the peak values are close – within five percent, and arriving the same engine speed – it`s clear the BMW`s output hangs in there better both above and below the point of maximum urge. This makes the M3 feel a little more flexible and accommodating.
As you would imagine, given the torque data and BMW`s weight advantage (2735 pounds to 3010), the M3 holds the performance edge over the 190. BMW quotes a 0-to-60mph time of 7.6seconds versus the M-B`s 8.1, and a top speed of 143, 6mph faster than the 190. Over the broad spectrum of actual down-the-road driving conditions, however, the two cars are quite evenly matched. Credit the ideal gearing Mercedes selected for the 190, and note that the BMW`s horsepower advantages are greatest above 6000rpm. Our testing confirmed that only when both drivers work extremely hard does the M3 pull ahead noticeably.
Of course, in larger race – the one in the marketplace – the BMW has pulled ahead solidly and for good. Disappointing sales and near duplication from the tamer six-cylinder 190E 2.6 finally killed the 2.3 16 in the United States. Yet there`s no question that the idea of a snarky-looking factory-hot-rodded sports sedan has enduring appeal. It might not make the ideal Mercedes-Benz. But look how it works as a BMW.
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June 2, 2008
1986 - 1989, Articles