- Apr 9, 2010
GSR Autosport BMW 350R: Part III - Testing, tuning and qualifying
GSR Autosport BMW 350R – Click above to watch the progress of the build
Formula DRIFT is recognized as the North American professional drifting championship series. Autoblog has been invited behind-the-scenes with GSR Autosport, and their driver Michael Essa, as the team builds, tests and campaigns a V10-powered BMW 350R during the 2010 racing season. This is the third installment in our series (see Part I and Part II) as we follow the team throughout the creation, testing and race season.
The BMW V10 ripped from an M5 and transplanted into a 3 Series does turn over on the first try – but then it starts to backfire. The GSR Autosport team shuts it down promptly and dials Apex Speed Technology. The engine and its related electronics are the most sophisticated part of the 350R. Its digital ECU is tasked with controlling fuel, spark, four-cam VANOS, dual drive-by-wire, electronic oil pumps and a variable-speed electric cooling fan. Without delay, the experts diagnose the problem (exhaust cams) and download a few fixes to the S85B50's ECU. Set straight, the BMW Motorsport engine growls without a hiccup.
Once the engine is warmed, Michael Essa does exactly what most of us would do – he takes the brand-new 350R for a celebratory spin around the block at the industrial complex and does screaming donuts in the middle of the empty street.
The car, still missing its front bumper, hood, roof and windows, isn't exactly done... but it needs to put some time in at the track to be honed. The team loads the 350R into a closed trailer and heads for Willow Springs International Motorsports Park in Rosamond, California.
Willow Springs Speedway, a quarter-mile paved oval, is the smallest track at the desert complex (not counting kart tracks). It's a lousy road course, but the open figure-eight is the perfect grounds for testing a drifter. Unloaded from the rig, fully fueled and running an engine map borrowed from a performance-tuned street M5, Michael takes a few hot laps to get a feel for the car. Then he takes many, many more.
Over the next several hours, shock settings are tweaked, springs are adjusted and tire pressures are both bled and increased. The final settings are as guarded as the recipe for Coca-Cola.
Power does not seem to be an issue, but weight is (lack of poundage, for better clarification). The 350R is light in the back (remember, everything was stripped out of the rear of the car while 50 additional pounds of V10 were added to the front), so the modified BMW is run with a full tank of fuel for more rearward weight bias. Content with the direction of the testing and tuning, everything is loaded back onto the trailer for the ride back to the shop.
The next visit is to the dynamometer. Strapped down firmly, the V10 puts up an angry fight and sends about 450 horsepower to the rear wheels. (Thanks to driveline loss and a rear differential utilizing a 10-inch ring gear that isn't exactly power efficient, our best guess says it is making an estimated 550-570 horses at the crank.) The team tweaks the ECU and finds some more power.
Two days later, the GSR Autosport 350R is getting painted. The exterior is sprayed glossy black, while the interior is shot bright silver (the lighter interior helps the in-car cameras with automatic white balance – no joke). The wheels receive a two-stage powder coat. They are coated in bright white followed by a garishly bright orange – Michael Essa's signature color. You can't miss them.
While stock bodywork is retained for now, a custom carbon-fiber widebody kit is being produced – it will shave another 100 pounds off the curb weight. Lexan windows replace the rear units, but the side quarter panels remain glass (the Lexan side windows only save two pounds each). Capping the drifter is a lightweight carbon fiber roof ordered straight off the E92 M3 parts sheet.
As you read this, the GSR Autosport 350R is sitting on the grid qualifying for the Formula Drift Round 1: Streets of Long Beach at the Toyota Grand Prix street course. Months of hard work, tens of thousands of dollars, countless individual contributions, and the generous help of sponsors have made the mildly deranged idea of drifting a V10-powered BMW 3 Series a highly-competitive reality.
We'll tell you how the team did next week.