2008 BMW 135i
Avg. Observed Economy: 22.6 mpg
We couldn't leave well enough alone. Despite a stock suspension that strikes a near-perfect balance between ride comfort and handling prowess, we tossed it all aside and installed aftermarket coilovers and a fat rear swaybar on our BMW 135i. Our motivation was partly cosmetic — we wanted to reduce the ride height just a bit and dial in more attitude. However, we also wanted to dial out some of the understeer that's such a buzzkill at the handling limits. Our only hope was that we wouldn't utterly destroy the day-to-day livability of our little coupe.
Our concerns were unfounded, as we quickly discovered. We went with a set of H&R Street Performance coilovers and replaced the 12mm factory rear swaybar with an H&R piece measuring 20mm. Despite lowering the car significantly, the primary ride characteristics remain largely unchanged; small bumps and pavement imperfections are soaked up easily. Second-order oscillations are shorter and stiffer for sure, but even on choppy sections of our least-favorite expressway the car never exhibits the kind of vomit-inducing, hippity-hoppity ride that is so common with super-stiff setups. Immediately after installing the springs and shocks, we sent our interns in the lowered car on a trek from Chicago to New Jersey and back, and they both returned not with complaints but full of praise for the well-sorted combination.
The bigger sway bar did its job as well, eradicating most of the at-the-limits understeer. The new setup rotates much better around the front of the car, allowing the driver to now steer with the throttle more easily. We actually installed and tested the new bar prior to any other chassis work to get a quantitative assessment of its effect as well. Running a six-cone slalom test both before and after, we ended up increasing our average speed from 29.6 to 30.2 mph.
In addition to the enhanced driving characteristics of the modified 135i, the height-adjustable nature of the suspension means we also got to fine-tune its physical appearance. We've set the suspension for a bit of rake from front to back, which we've all found takes the car from cute to purposeful, and the graphite-colored Breyton wheels heighten the dramatic effect.
With 15,000 miles now showing on the clock, the newness of the car is starting to wear off a bit. A slight knock has emerged from behind the instrument cluster over hard bumps. This was present before the suspension change, but has become more persistent since; we suspect it is the actual cluster where it mounts to the dashboard framework. The driver's seat is showing wear again on the upper bolster, but we knew that was going to happen. What we hadn't expected was a handful of random electrical glitches-turn signals that refuse to cancel themselves, one-touch windows that occasionally forget their one-touch functionality, and headlights that turn themselves on randomly, no matter what position the switch may be in. We have an appointment for our first scheduled service, and we hope to have those demons exorcised at the same time.
That first service won't be the first oil change, however. We couldn't bear the thought of going a full 18,000 miles on the original oil, as the car's on-board diagnostics were suggesting. At 11,000 miles (still crazy, if you ask us) we broke down and paid out of pocket for an oil change at the dealer. For a little over $70, it seemed like cheap insurance and set our minds at rest.
With summer nearing its end, we finally found the time to get it out on the track for some lapping sessions. We drove it out to a test-and-tune night at GingerMan raceway and let everyone have a turn with her. No one recorded times, unfortunately (our real reason for being there was to drive a Viper ACR with a couple of Chrysler's SRT staff), but the car proved easy to drive for even our novice staffers. The Yokohama s.Drive tires would not be our first choice for track duty (a bit greasy feeling, to be honest), but they held up remarkably well considering their treads were still essentially full depth. We also left impressed with the brakes, which softened only mildly in several hot laps and never once left us wondering if they had disappeared. Even on the drive home they exhibited none of the post-event shudder we've come to expect from other performance cars.
Thanks to the long drive, we've managed to bring our average fuel economy back up to around 22.6 mpg. The real challenge, though, is staying out of the throttle. The new suspension practically encourages you to power-oversteer every corner. Gremlins aside, the 135i has earned the respect of all who drive it, even the self-professed BMW haters. It's hard not to love this car.
2007 Audi S6
Avg Observed Economy: 15.6 mpg
Our six months with Audi's V-10-powered über sedan was neither perfect nor cheap at the pump, but the foibles weren't enough to cool us on this car. The S6 rewarded us with impressive performance and much more attention from others than we expected from a dark business-class sedan.
From the very beginning, we nit-picked some of the S6's personality quirks. The ride was harsh for a luxury sedan — a trade-off for making something this heavy so light on its feet. Fun in the corners, its performance over Chicago potholes or Pennyslvania post-winter concrete cracks was definitely a nuisance. The throttle was high-strung, making it hard to pull away from a red light without lurching. Even when the car's 6-speed Tiptronic wasn'tin Sport Mode, the Audi was difficult to drive gracefully.
Beyond its inherent peculiarities, we also experienced a few unexpected bugs like a fuel gage that perpetually displayed empty, an inoperative window switch and, just as we were about to turn it in, a trunk shock that only held the trunk lid partially open. All of these were but a nuisance, and each was fixed under Audi's factory warranty. One problem not covered by the warranty was a temperamental HID headlight. Oxidation on the bulb meant it worked some of the time, but not always. The catch? Bulbs are wear items, and thus not covered. A proper fix would have been over $300, but we were always able to rock the headlight switch back and forth to wake it into action. Yes, we elected to let the light go, knowing the S6 was about to leave our fleet anyway.
The cost of maintenance and fuel to keep the S6 on the road was eye opening. With more around-town driving in the last month, we averaged only 15.6 mpg, some of the lowest economy we've seen during our time with the car. During its stay we paid for one scheduled service, which included a tire rotation and a belly full of Mobil 1 at dealer book rate, amounting to over $800.
Some around the Motive water-cooler believed a sedan costing north of eighty big ones should be, you know, just a bit faster; a V-10 supersedan should be able to stomp all but proper exotics. Nevertheless, the S6 still possesses a wealth of emotional appeal. Notes during the last month of driving include everything from an A6-driving cougar shooting the crazy eyes at one contributor across a lane of bumper-to-bumper traffic, to a guy knocking on the window at a turnpike rest stop and wanting to sit in it. Despite a few niggles the S6 proved to be an excellent way to cover miles effortlessly, if not cheaply. It will be missed.