Porsche 911 v BMW M5 v Mercedes-Benz CLS 55 AMG 2006 Review

Surely if the Porsche 911, BMW M5, and Mercedes-Benz CLS 55 AMG were competing for Germany's spot in Eurovision '06, devil's advocate Terry Wogan would have nothing but praise for their song-and-dance routines. Indeed, the epitome of Kraut clout from Germany's finest car brands -- the Stuttgart crest, the blue-and-white propeller, and the three-pointed star -- are a very special breed indeed.

You'd bloody well hope the 911 Carrera, M5 and CLS55 AMG had something going for them, considering each costs more than 200 big ones, but therein lies the conundrum: to attain the finest in $220-250K German automotive entertainment, do you space-bag the family and go for a Porsche, include the kids but turn them white fanging a five-seat M5, or opt for an element of both in Mercedes' coupe-sedan CLS?

In terms of oily bits, no matter what your chosen weapon, you'll be thrilled to your back teeth with the forceful grunt and fabulous noise that the 911, M5 and CLS55 deliver. But each definitely has its own, delicately honed, flavour.

Fastest and most intriguing of the trio is the bullish M5. Not only does it produce the most power here (373kW at a staggering 7750rpm) and have the hottest power-to-weight number, it's also the world's first V10-engined sedan, beating Audi's imminent V10 S8 by a good 12 months. On paper, the M5's atmo 10 is an amazing engine. It runs a 12.0:1 compression ratio and demonstrates its near-insatiable desire for revs by not hitting its cut-out until 8400rpm. Arguably more impressive, however, is the V10's amazing tractability -- it delivers 450Nm from just 3500rpm before swelling to 520Nm at six-one...

All that mid-range torque makes you wonder why on earth the M5 would need seven (sequential) gears, but considering this maximises the time spent in its glorious pleasure zone, few would find cause for complaint (and that includes John Carey). What's most intriguing, though, is the engine's soundtrack -- raspy and metallic like an M3, but with much more meat. It sounds almost diesel-like at idle, but once on the move the V10 quickly changes character, delivering a Volvo-five-on-steroids (and countless amphetamines, plus any other high-NRG drugs it can get its hands on) effect.

WAKE THE NEIGHBOURS
It's no criticism, but the M5 really sounds like a manic S60 R in surround sound, with the bass wound right up. Only when the M5 clocks five-grand and then charges with urgency towards its 8250rpm redline does the similarity fade a little. But what the driver enjoys inside the cabin isn't necessarily what is conveyed to eager bystanders. The M5's exhaust rasp isn't as loud as the M3's, even though it produces an arguably more pleasant and polished noise.

If you really want to wake up an entire suburb, there's only one car here capable of doing it -- the supercharged CLS55. When its massively tough-sounding engine debuted in the SL55 AMG back in 2002, few could believe the blown V8 had actually passed noise regulations, so loud is its bellowing voice. And four years later, we're still relishing its magnificent hot-rod soundtrack and incredible, instantaneous grunt. You can hear the CLS55 coming from a mile away, and it won't take long to arrive, either, judging by its sub-five 0-100 time and 13-flat quarter-mile ability.

True, the M5 is ultimately quicker, but they're neck-and-neck to 80km/h, and barely 1.2sec apart at 180. What makes the CLS55, though, is its mountain-crushing torque -- a huge 700Nm from 2650-4500rpm, enabling it to punch from 80-120km/h in just 2.6 seconds. Only one auto we've ever tested has beaten that time -- Mercedes' own, slightly more powerful S55 AMG back in July '03, by an inconsequential tenth.

In comparison, the 911 Carrera's 239kW (at 6800rpm) and 370Nm (at 4250) seem almost anaemic, as does its 171kW/tonne power-to-weight figure. But only those who've never enjoyed a rear-engined rear-driver would discount the Porsche's inherent traction advantage when launching from a standing start. Rev the 911's gorgeous flat-six to its max power point, then dump the clutch, and it claws tarmac as well as any WRX or Evo, but smoothly, and much less brutally. Even in base, 3.6-litre form (we failed to snare a manual 3.8-litre Carrera S), the Porsche is the fastest of the three to 60 and is so close in most other disciplines that the M5's 2.3sec advantage to 180km/h is purely academic in an Australian context. In all honesty, anyone who needs more power than a regular 911 is simply being greedy.

SUPER SYNERGY
At any speed, the 911 is superbly driveable, with unmatched synergy between clutch-pedal weighting, brake feel and throttle response. Yet the harder you drive it, the brighter it shines. The Porsche needs 3000rpm showing on its large, centre-mounted tacho before it really hits its stride, but from there, right to its 7200rpm redline, the 911 gathers speed with exponential intensity, accelerating harder and faster at every moment, and simply begging for more. But what really defines the 911 experience is its purity. From the exquisitely crafted wail of its wonderful engine to the tactility of its superb six-speed manual gearshift, neither the Bimmer nor Merc can match its intimacy.

With the Benz, this is less of a concern. The torque-laden CLS55 is an athletic, balls-out cruiser that suits an automatic transmission (a very fine five-speed one at that, with steering wheel shift buttons behind each top spoke -- left one for down, right one for up). The M5, on the other hand, is much more of a true sports sedan, but also one that inevitably deprives its driver of ultimate interaction by virtue of its sequential SMG 'box and two-pedal layout. Compared to the supreme satisfaction acquired from manually actuating all of the 911's controls, and even the old E39 M5's manual shift, the SMG-equipped E60 almost feels a little clumsy. No argument that for track days and hardcore cornering, the seven-speed 'box (with column-mounted shift paddles) is brilliant, but it ultimately detracts from the driving experience.

That said, the M5's SMG III is a huge improvement over the M3's flawed SMG II iteration -- still a tad jerky in town in auto mode (despite six different shift-speed settings), but much smoother and more responsive. We drove it manually most of the time (using the stubby alloy console shift knob), though, relishing the SMG's newfound ability to throttle-blip properly on downshifts. Nudge the lever down two gears and the M5 responds with an addictive 'braaap' from its throaty V10 as it matches revs to suit. In auto mode, the 'box still downchanges with a lovely blip of the throttle, but the slight jerkiness as it changes up, combined with the M5's grabby brake response, means smooth town driving is always an exercise in delicacy.

But as the road opens up and the traffic thins, the M5's sensitivity becomes a positive. Its serving-platter-sized brakes -- 374mm ventilated and drilled discs in the front, with 370mm of the same out back -- inspire unwavering confidence and do a tremendous job of hauling up 1755kg. The M5 also has noticeably more brake feel than the slightly average CLS, and a much higher ABS threshold, too -- the Benz pedal chatters long before its faster BMW rival. The CLS's slightly inferior brake spec (ventilated and drilled discs, 360mm front, 330mm rear) and 90kg weight penalty obviously do it no favours. But, again, it's the 911 that really stands out here.

The Porsche's stopping potential is enormous -- its ventilated and drilled discs (318mm front, 299mm rear) delivering crisper, more progressive feel than the M5's awesome brakes. The 911 has a lower centre of gravity, too, and substantially less bulk than either sedan (it weighs 360kg less than the M5), and the benefits in braking and dynamics are palpable.

CHOOSE SPORT
The first impression gained from driving the 911 is its beautifully weighted, super-crisp steering. With minimal weight over its nose, the Porsche's lovely three-spoke wheel has a light, delicate feel. While it lacks the off-centre reactivity of older 911s, the new 997's variable steering ratio means it provides faster response as more lock is applied, and is also faster-geared from lock to lock (2.6 turns versus the old 996's 3.0). But where the 911 truly rounds up the sedans is on really tight, winding roads. It simply feels so much lighter, turns in far more aggressively, and pivots on a much tighter axis thanks to its short wheelbase. With its fat rears tyres (295/30ZR19s), wide stance and rear-mounted engine, the 911 can get its power down earlier in a corner, too, squatting the tail, drifting its rear slightly as it passes the apex and then spearing out, demonstrating its brilliant traction. And that's in PASM's 'Normal' mode. Choose 'Sport' and the 911 becomes an even sharper weapon, firming up its dampers for a more tied-down front end, a slight improvement in steering feel and response, and reduced body roll. True, its 'Sport' suspension feels very rigid and can buck the car around over bumps, but there's no crash-through and it never really feels uncomfortable. Other brands might do switchable dampers, but none seems as perfectly suited as a 911's.

Those 'others' include BMW and Mercedes-Benz, whose M5 and CLS55 both employ electronic dampers with three distinct settings. The M5 offers the widest range of variance, with EDC's Comfort delivering an unexpectedly absorbent ride quality, as well as lighter weighting for its Servotronic (non-active) power steering, quite a bit of body roll in corners and noticeable pitch under acceleration and braking -- at least relative to its performance in 'Normal'.

Unless punching along concrete freeways or pottering on really bad surburban roads, 'Normal' best defines the M5's character (super-stiff 'Sport' is best reserved for racetracks). Here, its steering is much meatier (but not too heavy), it rolls barely at all, and its overall body control is vastly superior. Ride quality becomes very firm and jiggles the car around a little on bumpy corners, but corner-exit traction is superb and the M5 genuinely belies its size and weight by packing the agility of something much smaller. Balance is amazingly neutral, and fast-sweeper cornering grip is immense -- the lack of active steering making the hardcore M5 feel nicely progressive and really confidence-inspiring at insane speeds. Thrilling as the M5 is, however, it ultimately can't match the 911's steering interaction or its supreme throttle adjustability in tight corners.

The slightly disappointing CLS55 lags well behind the M5 for agility. It feels heavier and much more understeer-biased, although it's nicely balanced in fast, 75km/h-plus corners and neutralises its attitude as you feed in power. In its 'Sport 1' setting, the CLS rides better than the M5 in 'Normal', while providing an equally pleasant ride with its dampers set to 'Comfort'. But even the Porsche rides quite well on its standard setting. The CLS lacks the M5's brilliant body control and feels looser on the road, while needing to be driven well to be super-rapid, and clearly prefers the slowish-in, ballistic-out approach. But what lets the Benz down the most is its steering. The CLS55's lovely AMG steering wheel frequently judders in your hands and kicks back over bumps, just like the E55 and SL55. It also goes stiff when cornered hard, and can prove reluctant to turn in just at the moment when you require steering response most, which can be scarily disconcerting. As a rapid cruiser, the CLS55 is king, but for a sporting car packing so much grunt, its dynamic flaws tarnish its desirability.

Accept its limitations, though, and the CLS55 is a special car. Sure, it's only a four-seater, with nothing like the M5's rear-seat headroom (180cm bodies are about the Benz's limit) or its seat comfort (the CLS's rear cushions are a tad short, whereas the M5's roomy rear pew is beautifully supportive). But despite its shallow side-window line, the CLS's dash cowl is quite low, making for a great view forward, and no-one can ignore its frameless-windowed, chopped-roof style.

CHALLENGE AND REWARD
The low-slung 911 has tremendous vision in all directions and a tough yet classic elegance that's rare in being both modern and timeless. The M5, on the other hand, is a sizeably pumped version of a slightly awkward-looking sedan (the E60 5 Series), and mixes its donor car's impressive five-seat room with enough body-bulges and exhaust pipes to effect a semi-Hulk-like transformation. She mightn't be pretty, but check out the muscle.

And, surprisingly, BMW's bully is almost a what-you-see-is-what-you-get proposition -- $229K with only seat ventilation ($2750) and a ski port (er, $1100) causing further wallet pain. The CLS55 is $20,000 dearer, which means bugger all, but there's still $26,730 worth of gear left to go, including stuff that should be standard (such as $690 folding mirrors). In contrast, the Porsche's even more extensive and extravagant options list is countered somewhat by the fact the base Carrera costs $54K less than the CLS.

Is the CLS55 really worth the extra dough? Probably, if you're mad about Mercs and couldn't give a Charlie about whether it's a gun handler. It isn't, but the CLS55 is an amazingly effortless car to drive fast, and a supremely cool and comfortable car to cruise in. And the sound! Highlight by far is its monster engine and the accompanying Rammstein soundtrack -- arguably the finest V8 noise in the world.

The M5 isn't relaxing like the CLS -- it's a little frenetic, due to all those revs and all those gearchanges. But it slaughters the AMG coupe-sedan (and any other) dynamically, is more comfortable, more practical, and, er, more affordable. But delectable as the V10 is, if only it delivered more noise, and if only it came in a manual.

The Porsche, on the other hand, is near-perfection for a sports car. It's everything you want it to be, yet has this sublime challenge-and-reward nature that begs you to wring the best out of it. For depth, few can match it. Even the flat-six's characterful whirring as you park the 911 becomes addictive, let alone the glorious wail it sings when giving its all. If M5 and CLS55 are not quite meeting their Waterloo here, the 911's victory is still convincing.

Images: Cristian Brunelli