The BMW Z4 GTE sweeps past on the banking at Daytona International Speedway, making its grand entrance in America just a few weeks before the first ALMS race of the season, the Sebring 12 Hours. As we look down into Turn 1 and hear echo of the exhaust from car’s V-8 engine, we can’t help but want to be in the driver’s seat.
This isn’t an entirely foolish ambition. A surprising number of carmakers are building (or offering to build) versions of their cars for road racing, including Aston Martin, Audi, Bentley, BMW, Corvette, Ferrari, Lamborghini, Nissan, Porsche, and, well, you get the idea. Several even organize testing session, where you can take a turn at the wheel and maybe leave the track today with a brand-new car!
Speed in Series Production
Sadly we won’t be leaving Daytona today with a new BMW Z4 GTE, but such a thing will be possible some day soon. For years BMW has built cars in relatively large quantities for various touring car championships around the globe, and indeed you go right to the official BMW Motorsport site to see what’s on the sales lot, so to speak.
Just like BMW Motorsport cars have always been, the BMW Z4 GTE is built to a standard that rival crew chiefs describe as, “magnificent.” This car expresses not just BMW’s interest in motorsport but also its corporate culture – a dedication to doing things properly.
The BMW Z4 GTE will be raced in the American Le Mans Series (ALMS) by Rahal Letterman Lanigan Racing, BMW North America’s partner in racing, which is familiar as the winner of the ALMS GT class in 2010 and 2011 with the Team RLL BMW M3 GT. BMW shifted its world-wide sports car racing efforts to the Z4 GT3 in 2010, which has helped increase the performance credibility of BMW’s only sports car, and now the car has been modified for the ALMS rulebook.
European Style, U.S. Calibration
Compared to the BMW M3 GT raced in the ALMS over the past few years, the new Z4 GTE is a smaller package, measuring 173.0 inches in length, 79.1 inches in width and 47.4 inches in height on a wheelbase of 98.3 inches. With its steel unibody core from the Regensburg plant where the standard BMW Z4 is manufactured and a complement of carbon-fiber pieces for the hood, fenders and roof, the Z4 GTE weighs 2745 pounds.
Compared to the M3 GT, this new car is much lower yet much wider, so the aerodynamic frontal area is about the same. At the same time, the Z4’s low, narrow greenhouse helps more turbulence-free air to stream onto the rear wing than the M3’s cabin allowed.
The Z4’s relatively flat bodywork also holds out the possibility of optimizing low-speed downforce for the ALMS’s tracks in the U.S., which are generally slower than those in Europe and include street circuits.
Powered by a V8
Just like the M3 GT, the new car carries a V-8 engine, a 4.4-liter example with a stock block from the BMW foundry at Landshut. The engine makes about 475 hp, revs all the way to 9000 rpm, and runs on E85 gasoline. As the Z4 GTE goes past us, the note from the V-8 also sounds very different than that of the M3 GT. In fact, this BMW sounds like a NASCAR stock car, and NASCAR president Mike Helton smiles approvingly from pitlane where he has come to watch the ceremonies.
It turns out that the rulesmakers proved reluctant to endorse the expensive, free-breathing M3 GT V-8 with its racing-type 180-degree crankshaft, so the Z3 GTE V-8 has a conventional crank layout. The engine not only sounds different but also shakes far less, so fewer parts should rattle off the car. A sonic restrictor in the intake system required by the rulesmakers controls the engine’s power output.
The V-8 is paired with a sequential-shift six-speed manual transmission, and the gearbox is controlled by shift paddles on the steering wheel.
Drive, They Said
It might come as a surprise to you, but these days racing drivers like anti-lock brakes and stability control. Maybe that’s one reason the rulesmakers say the BMW Z4 GTE must do without them, even though they’re standard equipment for the GT3 version.
The drivers will have plenty to think about, because the driver’s seat is now almost right on top of the rear axle, and this position creates an entirely different sense of the car’s dynamics. It’s a little bit like driving an M3 from the back seat while aiming the nose of the car through a gunsight. There are also additional challenges in the Z4 GTE because the car’s weight distribution now sits at 50 percent front/50 percent rear. This might be fine in a street car, but it isn’t even close to the M3 GT’s impressive weight balance of 46 percent front/54 percent rear, a proportion that Team RLL worked hard to achieve during its development of the car. The Z4 GTE’s drivetrain doesn’t allow for the same redistribution of components, and the rear of the car is already crowded with the 29-gallon fuel cell, so some challenges might lie ahead.
Fortunately for BMW, it’s partnered with Michelin this season, and the tire company’s new regional-based operational structure for its racing efforts should allow the U.S. group to mix and match tire constructions and compounds to suit the Z4’s special issues. The car wears 300-680-18s in front and 310-710-18s in the rear on forged BBS wheels.
Better Than F1
Unlike Formula 1 cars, sports cars are all different. In fact, this is the best thing about them, since each one represents a different answer to the question of high-speed physics.
Even better, sports cars are also relatively accessible to ordinary mortals. That is, if you can describe the official $440,000 price tag for a BMW Z4 GT3 as, “accessible.” (The price of the GTE version has yet to be determined.) Nevertheless, you can aspire to drive such a car, and carmakers like BMW, Porsche and Mazda even have a kind of ladder of racing championships that amateur drivers can climb. And at the top rung, there’s the prospect of driving in the 24 Hours of Le Mans.
It’s enough to make road racing seem like fun, isn’t it? That’s certainly what we thought as we watched the BMW Z4 GTE drive past on the Daytona banking.