Comparo: BMW M Roadster vs. Porsche Boxster S
Story and photos by John LeBlanc
Which of these two Teutonic two-seaters is the most thrilling to drive?
While Mazda is responsible for the return of the modern roadster with its 1989 Miata, and other two-seaters like Audi’s TT and Mercedes-Benz’s SLK have come on the scene as well, all pale from the driver’s seat compared to our two Faceoff combatants.
Eight years after the original Miata’s (now known as the MX-5) sales success shook the industry, Porsche beat BMW’s Z3 roadster to market with its Boxster (a confluence of “Boxer engine” and “roadster”) by one year.
Designed from the outset as a convertible (all previous Porsche ragtops started out as hardtop coupes), the Boxster further distinguished itself by placing its engine in the middle of its chassis, as opposed to the Bimmer’s more traditional front-engine design. Along the way, Porsche has continually upgraded the Boxster with larger engines and subtle styling teaks.
A successor to the original Z3-based M Roadster produced between 1998 and 2002, today’s version, introduced in 2006, is based on the newer Z4. As the
Cayman is to the Boxster, there is also a hardtop version called—you guessed it—the M Coupé.
As BMW is in the throes of replacing its Z4 roadsters and coupes with a single model retractable hardtop coming next year, this will be the last year to get a cloth top BMW roadster. And the Boxster is yet again due for another update before the end of this year.
So which of today’s dynamic roadster duo is the most thrilling to drive?
SECOND PLACE: 2008 Porsche Boxster S
Unlike the M Roadster that was born from more plebeian BMW 3 Series bits and bolts, you can find plenty of exotic rear-engine Porsche 911 Carrera in the mid-engine Boxster.
In fact, having grown in displacement from the original 2.5-litre flat-six-cylinder engine in the 1997 model, today’s $70,200 Boxster S is powered by a 295 hp 3.4L unit; an engine that until five years was essentially the same motor in big brother 911.
Like its hardtop Cayman S stable mate, standard transmission choice is a six-speed manual gearbox; one more gear than in the $12,100 less expensive Boxster 2.7. A $4,490 six-speed automatic is available. But what roadster fan would want to miss out on the opportunity to fully realize the thrilling sound of a legendary Porsche flat-six? Plus, the Boxster S’s clutch pedal is much lighter and easier to use than the BMW’s, with short throws and surgically accurate gear placement.
Compared to the BMW’s more traditional engine-up-front chassis design, without a doubt, the placement of the Porsche’s engine is the overwhelming characteristic that determines how it goes down the road. It also makes the Boxster S the easier car to drive fast.
The Porsche's mid-chassis design means there are less centrifugal actions tugging on your intentions when connecting apexes on a back road. And unlike the M Roadster—where its overtly buttoned down suspension means every road irregularity is an adventure—mid-corner bumps in the Boxster S are never a concern. Although Porsche's variable-ratio steering seems to anticipate the driver's intentions telepathically, like a 911 it shares its front end with, it sometimes can get too light at high speeds.
But helping the Porsche’s cause is it’s lithesome body. At 1,354 kg, it’s a good 100 kg lighter than the BMW. Not only does that equate to better economy (about a 20 per cent improvement over the BMW at 11.8L/100 km city, 7.7 highway), every input from the driver receives a quicker reaction from the car than in the porkier Bimmer.
Despite having less mass to haul around, the Porsche can’t beat the more powerful BMW in a straight line The M Roadster’s extra engine mojo equates to a better power-to-weight ratio. Accordingly, zero to 100 km/h in the Bimmer takes about a half second less than in the Boxster S, which is no slouch at 5.4 seconds.
BUY THIS CAR IF ... you want to drive fast right out of the box; want to enjoy sublime on-road handling; experience one of the best gear shifters in the biz; save gas.
DON'T BUY THIS CAR IF ... price and straight-line performance are at the top of your priority list.
FIRST PLACE: 2008 BMW M Roadster
Plain and simple: The heart won over the head here when it came time to picking the most thrilling roadster between this German duo. Where the Porsche is technically an easier roadster to drive, the BMW—with its stiffer suspension and explosive straight-six engine—is in the end more challenging (and more rewarding) when you get it right.
Also rewarding is the BMW’s cost advantage. Starting at $70,200, the Boxster S’s base price is about $6,000 higher than the M Roadster. As tested, the Porsche still was a healthy $78,420 versus $69,100 for the BMW.
Under the M Roadster’s hood, you’ll find the same 3.2-litre straight-six engine from the last M3. It pumps out a healthy 330 hp and 262 lb-ft via a six-speed manual gearbox. If you want an automatic, shop elsewhere. The stick is the only tranny available in the BMW.
With such a robust powerplant, the M Roadster literally explodes off the line, squatting and squirming while looking for traction. Compared to the calmer Boxster S, it’s old school sports car fun.
With a suspension better suited for track days, though, the M Roadster’s nemesis are pockmarked and potholed roads. It can be a handful at speed on anything less than perfect pavé. And where the balanced nature of the Porsche’s chassis makes it easy to drive fast, you have to be alert and treat the BMW like the ruffian that it is. “Point and shoot” ends up as the recommended driving strategy, mainly because in the tighter corners the roadster will understeer and ask for more steering input than the Porsche.
OK. The BMW’s a beast. But taming it is half the fun. And buyers looking for refinement and governments looking for more fuel efficient and cleaner cars are weeding out raw rides like this quickly.
My advice? Enjoy the M Roadster while you can.
BUY THIS CAR IF ... you want a classic roadster driving experience; track-ready suspension; and explosive performance.
DON'T BUY THIS CAR IF ... if your little tushy can’t handle a stiff ride.