Roadster Renaissance - Three versions of tuned, topless fun
By Les Bidrawn and Brendan Lopez
My older colleagues reminisce about how great it was "back then," when a rickety convertible, an open stretch of highway and a few bucks
in your pocket was the road to true happiness. They tell me life was more simple then, music was better, people were nicer, cars were cooler.
Well, shove another 8-track into the tape player and move out of the way, you geezers, because the new generation of roadsters is here, and they're quickly obliterating any feeling that we younger enthusiasts missed our chance at the good life.
The 90's is ending is a crescendo for car lovers, and the three gorgeous chunks of metal featured on these pages serve to define our
generation's automotive moment in the sun. With singular styling and exhilarating road manners, these cars inspire the same passions
that cause glazed eyes in my more mature colleagues when they wax nostalgic about the great open cars of yore. I think today's buyer has it a lot better:
There's still that passion which can make a simple trip to the grocery store an event to be remembered but, more importantly, these modern cars do it better that their forefathers, with superior reliability, more luxury and, above all, with more exciting performance.
On one fine summer day, high up in the mountains outside of Los Angeles, european car assembled a trio of exciting variations ofthe roadster theme, based on the BMW Z3 2.8, Mercedes Benz SLK and Porsche Boxster. All came to the party dressed to kill and were chock full of cutting-edge tuner technology.
In tribute to the older generation, we installed a "Route 66" CD compilation in the changer and did our best James Dean impersonations trying
to look really depressed. It lasted a few minutes before the staccato exhausts echoed throughout the canyon and "The Distance" by Cake lasted over the stereo.
Not so long ago, the words "flexible" and "turbo" would never have been placed in the same sentence. Though great fun in their time, older turbocharger systems took significant time (turbo lag) before unleashing their furious rush to the rear wheels. And in terms of fwd configurations, that blast of boost would likely yank the wheel right from the driver's hand. We learned to live with it, though those were the prices of admission for a forced-induction system.
Things are different today a lot different. Significant advances in both engine management and turbocharger configurations have blessed forced-fed cars with remarkably linear power curves, making turbos or blowers nearly transparent in their contribution to engine power. Such is the case with the MechTech Motorsports Z3 2.8 Turbo. It's a car that seamlessly blends a furious, turbocharged rush and remarkable flexibility. With its greatly expanded capabilities, the rear end claws for purchase if the throttle isn't moderated by good sense. It's a car where the driver's right foot dictates the car's direction almost as much as the steering wheel. Closing the distance from point A to point B is an exercise in unnerving brevity. Out of the three cars assembled that day, the BMW was numerically superior in horsepower. Need some hard numbers to chew on? Try 300 hp at 5500 rpm and a cervicle-crunching 334 lb-ft of torque at 3200 rpm. The sprint to 60 mph takes a scant 4.9 seconds, and the little roadster covers the ? mile in 13.2 seconds at 107 mph. Most rewarding, though, is the way the power comes on with a silky smoothness.
"A simple, yet elegant turbo system design", says Jim McFarland of MechTech Motorsports.
"From a system design standpoint, the MechTech turbo system is actually very simple," said MechTech's Jim McFarland. "The key to its success lies
in the flexibility of the unique, variable vane, self-contained and self-lubricating turbocharger. We're into full boost by 1800 rpm; there's no
waiting for the thing to spool-up; just press the throttle and go," he added.
Though McFarland downplays the complexity of his system, its underlying simplicity is very trick. There's no drilling, cutting or hammering involved in its fitment. The turbocharger is the highly sophisticated VATN unit, an entirely self-contained turbo that functions without feed lines from the block and oil pan. Moreover, the moderate 5 psi boost means the factory's engine management program and fueling system remains largely the same.
"The bolt-on aspect of the system is very important," said McFarland. "With 65 to 70 percent of all BMWs leased, owners are reluctant to install complicated performance equipment that's difficult to remove once the lease is up. The MechTech Turbo system can be bolted on I emphasize bolted on in about eight hours with an ordinary set of metric tools. That time would be even shorter for a mechanic of average skill level. Taking it off is even easier."
The MechTech Turbo system is comprised of a VATN turbocharger, cast iron exhaust manifold, turbo downpipe, upgraded fuel pressure regulator, 2.0-in. aluminum intake tubing, 2.5-in. exhaust tubing, silicon connectors, high-grade clamps, aluminum intercooler, boost gauge and high-flow K&N intake element. There's no need for blow-off valves; the variable vanes of the turbo eliminate unnecessary pressure. This particular car was also equipped with a MechTech stainless-steel exhaust, a cat-back system featuring mandrel-bent 2.5-in. tubing and a 4.0-in. tip. The sound was deep but never intrusive, and it served to accentuate the interesting tonality of the turbo's variable vanes. As their pitch became more aggressive, the aural sensation was very reminiscent of an aircraft, similar to that in the cabin of a luxurious, yet very quiet, turbo-prop.
In terms of quality, MechTech appears to have done its homework. "We've clocked more than 5,000 miles on this car, and the turbo system has performed perfectly," McFarland reported. "Moreover, the OBD-II system is quite happy; we've yet to see a fault code,"
Currently, MechTech is undergoing the certification process to make the turbo system 50-state legal and provide it with an E.O. number. "I don't foresee a problem with the MechTech Turbo system passing the test," stated McFarland. "Tailpipe emissions have remained clean, and we should have the E.O. in a few months. MechTech Motorsports has been doing high-end performance work for 11 years, specializing in forced-induction systems and chassis tuning. MechTech is currently working on a program that will wring and additional 20-some hp from BMW's straight six, power derived from a simple Motronic upgrade and exhaust. "This program, like the turbo system, is very non-intrusive," said McFarland. "And results are pretty dramatic considering the amount of hardware required." Dramatic performance without dramatically alteration it's a concept MechTech has refined. L.P.
