May 18, 2006 - If you think selling umbrellas in Vancouver or bottled water in the Sahara are easy business decisions, think about the BMW product planner who came up with the idea for their new M Roadster?
 
“Let’s see now. How about we take all the juiciest parts from our highly-regarded M3 Coupe (that would be the engine and the suspension, OK?) and stuff them into our sexy, yet underpowered Z4 Roadster. Wadda you think?”

Er, seems like a no-brainer to me. The updated-for-‘06 rear-drive Z4s come with 3.0-litre versions of BMW’s already sweet, straight-six-cylinder engines—the most powerful iteration making 255 horsepower. They are nice cars to drive. Really. But if you think the words nice and cars don’t belong in the same sentence then you’ll agree that the decision to stuff the M3’s demonic 3.2-litre DOHC 24-valve straight-six into the formerly gentile Z4 roadster is a way better idea than the pairing of The Captain with Tennille.


 
Compared to the donor M3’s powerplant, horsepower is down in the M Roadster’s mill by three, to 330, caused by the more restrictive exhaust plumbing due to the Z4’s smaller size. Don’t worry; you wont miss the three missing horses. After firing the M Roadster up for the first time, within half a block it becomes obvious what this car’s all about is heavily thrumming between its front wheels.
 
Beyond the M Roadster’s inherent configuration that has you sitting virtually on its rear axle, looking over the hood like Ben Hur admiring his steeds, the engine’s racecar-like mechanical whine is louder and prouder than in the M3. The maximum 262 pound-feet of torque available at 4,900 r.p.m. delivers instant urge—whenever, wherever—via the immediate throttle. According to BMW’s numbers, the lighter by 99 kilograms M Roadster, at an even five seconds, is quicker accelerating to 100 kilometres an hour than the M3 by 0.2 seconds.


 
No-brainer number two has to be the swapping out of the Z4’s suspension—shocks, springs and anti-sway bars—with a firmer setup that’s comparable to what’s found under the M3 Competition Package. In addition to BMW’s Dynamic Stability Control (DSC), the M Roadster gains stronger wheel bearings and heavier subframes to incorporate BMW’s variable differential lock. BMW M's floating compound high-performance brake system—developed first for the European market-only M3 CSL—means the M Roadster’s stopping measures are equal to its accelerative powers.
 
Despite all of this nifty hard- and software, given the right conditions (i.e. turning the DSC off on a dry back road) the M Roadster can be slid around corners, but the car’s first inclination is to initially understeer. Once the new M differential engages, power oversteer can be found smoothly through the judicious use of your right foot.
 
It might be a tick slower, but one area where the donor M3 still has the upper hand over its two-seat sibling is in the steering department. Where lesser Z4s make do with the standard electronic steering setup, the M Roadster reverts to a more traditional hydraulic system. Turn-in is instantaneous with precision, and feedback is more consistent than the previous Z4. But compared to the near-perfect helm of the M3, there’s still too much weight, making you pitch the M Roadster into tight corners with needed aggression.


 
The steering seems to be the only fly in the M Roadster’s driving ointment, because overall, body roll is negligible. Tying together a series of switchbacks comes with ease. Although there’s less wheel travel than the M3, resulting in a very busy ride quality on roads that haven’t seen a paving crew since last fall, the M Roadster is way less shitterish than the Z4 when its mettle is being tested. Some of the credit should go to the Continental ContiSportContacts (need to confirm) instead of the harder compound run flats that Z4s wear.
 
Just in case you were wondering, you better know what the M Roadster’s third foot pedal on the left is for as the sole transmission choice is a short-throw, six-speed manual gearbox. Inside the M Roadster you’ll find M badges sprinkled on the speedometer, tachometer, steering wheel, gearshift lever knob and door sills. As with the regular Z4, the driving position is excellent. My only gripe is that the diameter of BMW’s M steering wheels tends to be almost too thick to grip with ease.


 
OK, it may have been an effortless exercise to create the M Roadster. I mean, how many focus groups did the Bavarian company need to green light this puppy? The bonus is a car that appeals for its raw and dramatic driving characteristics. If anything, with the next generation M3 moving to a V8, in the new M Roadster the world-class six has a home in the near term.
 
I’m not sure the new M Roadster betters the on-the-road capabilities of the benchmark Porsche Boxster S. But the BMW demands a driver of higher skill, which for some, is a challenge worth taking on. And like a condom kiosk in Ft. Lauderdale during March break, creating the new M Roadster is a no-lose business proposition. Whoever came up with the idea back at BMW HQ in Munich, Germany, can take the rest of the year off.

-John LeBlanc, Publisher, www.straight-six.com



Just the facts…

Build quality 
Features  
Performance 
Fun-to-drive
Overall value

TYPE OF VEHICLE: Front-engine, rear-wheel-drive, 2-passenger roadster
ENGINE: 3.2-litre DOHC I6, 24-valve
POWER: 330 h.p. @ 7,900; 262 lb-ft of torque @ 4,900 r.p.m.
TRANSMISSION: Six-speed manual
BRAKES: Four-wheel disc with ABS Dynamic Brake Control included in Dynamic Stability Control
PRICE: BASE/AS TESTED: $69,900/$72,800
FUEL ECONOMY: L/100 km 14.6 city, 8.9 hwy.
OPTIONS: Premium package $2,900
STANDARD FEATURES: Xenon headlights, M mulitifunction steering wheel, heated M sport seats, Nappa leather upholstery, tilt/telescopic steering wheel column, HiFi 10-speaker sound system, in-dash CD/MP3 player, onboard computer

© National Post 2006. This article originally appeared in The National Post's Driving.