Effective Execution

Turner Motorsport ups the sport in BMW’s latest sport sedan, the F10 M5.

Photo: Effective Execution 1
January 15, 2015

Will Turner has been buying new BMWs for decades, but the owner of Turner Motorsport had never taken European delivery until last fall, when he picked up the keys to a new F10 M5 at the BMW Welt in Munich.

“The whole experience is awesome!” says Turner. “I would recommend it for anyone who can do it. They really make you feel special.”

Turner wanted more than just an awesome experience from European delivery: He also wanted to break in his new M5 on some of Europe’s best roads, including a few Alpine passes and the famous Nürburgring Nordschleife.

“We put 2,300 miles on the M5 in about a week in Europe,” he says. “The traffic was so good in Germany that we were running at top speed for hours, with the head-up display showing 174 mph, but it was hitting the limiter. The car was perfectly stable at those speeds, and that was pretty impressive.”

Photo: Effective Execution 2

More important to his development of the car, however, were Turner’s laps of the Nürburgring.

“The first lap was getting a feel for the car,” he says. “It was very fast on the straights and didn’t have a big push [understeer] like I thought it would, but I knew we could improve the handling and give it more power once we got it back to our shop.

“On the second lap, I turned traction control off and tried to go faster. I thought the brakes would fade right away and they didn’t, but they were not as grippy as I like and needed more feel from the pads. Another problem is that the M5 doesn’t make any noise, and I like to hear the car.”

Naturally, Turner planned to address all of those issues. His Amesbury, Massachusetts shop is best known for tuning M3s and other 3 Series BMWs, and for racing them with great success, but TMS isn’t new to the M5. In fact, this F10 is its third M5 project car, and it’s one that Turner himself was especially keen to build thanks to its twin-turbo S63 V8 engine.

Photo: Effective Execution 3

“I knew the new M5 would be tunable with the turbos, and I knew it would make so much torque that it would be a good drive,” says Turner. “In the E60 M5 with the V10, the best part of it was winding the engine out but the worst part was that it didn’t have any low-end punch. I assumed the new M5 would have both low-end and top-end.”

An M5 for hardcore enthusiasts

Once the M5 had crossed the Atlantic, Turner didn’t waste any time upgrading its performance and handling to appeal to hardcore enthusiast drivers. He was happy with the Electronic Damper Control’s balance between ride comfort and handling, but he figured it could be better still with a set of H&R Sport springs in place of the stock springs. The H&Rs lower the car by 1.0 inch at the front and just over 0.5 inch at the rear, giving better weight control and improving the M5’s appearance by narrowing the gap between the tires and fenders for a more hunkered-down stance.

To address the brake feel that had disappointed Turner at the Nürburgring, TMS left the (standard, non-carbon ceramic) calipers and rotors as delivered but replaced the stock brake pads with Pagid pads designed to withstand higher temperatures in track use and have more consistent pedal feel.

Photo: Effective Execution 4

The M5’s S63 V8 looks better under the hood than most of the other modern BMW engines, but TMS dressed up the engine bay and improved air flow by installing a Gruppe M intake. Manufactured in carbon fiber, the intake is designed to direct air from the rear of the front grille directly into the intake manifold, increasing air flow enough to add around 10 hp and 15 lb-ft of torque. The carbon fiber intake hardware also looks fantastic under the hood, with fit and finish that rivals the OEM pieces.

Engine breathing was further improved and the lack of sound addressed with Turner’s own axle-back exhaust, which deletes the rear mufflers to give the M5 a much more aggressive tone while adding around 14 hp and 19 lb-ft. As a bonus, the deletion of the rear mufflers reduces weight by 15 pounds.

All of BMW’s turbocharged engines can see substantial power increases with the right software tuning. TMS installed its Performance Module, which plugs in ahead of the engine computer on the wiring harness and adjusts fuel and ignition mapping as well as turbo boost to add 87 hp and 70 lb-ft of torque. Based on dyno runs of an M6 with the same upgrades, TMS estimates that this modified M5 is making around 600 hp at the rear wheels.

The M5 looked a bit too stealthy for Turner’s taste, so TMS enhanced its appearance by adding a Vorsteiner carbon fiber front splitter and rear diffuser (after our action shots for this story), as well as a black kidney grille, black side grilles and white taillights. The black accents, in particular, look great against the Frozen Grey paint.

Photo: Effective Execution 5

Topping off the styling changes is a set of 21-inch Vorsteiner VS-340 wheels in place of the stock 19-inch wheels. The Vorsteiners measure 9.5 inches wide at the front and 11.0 inches wide at the rear, mounted with 265/30-21 and 305/25-21 Michelin Pilot Super Sport tires. The wheels are manufactured in aircraft-grade aluminum with an aggressive seven-spoke design, with black centers and brushed aluminum outer lips

In the cockpit, the only change is the addition of a P3Cars Digital Interface integrated into the left front air vent. This device can display a wide range of data, including turbo boost, fluid temperatures, intake air and exhaust temperatures and battery voltage.

Noisy, impractical and irresistible

The stock M5 is fantastic, but approaching it doesn’t send a tingle up your spine like the TMS car does. The combination of carbon fiber body pieces, large wheels and tires and fat exhaust pipes give the M5 a menacing appearance that makes it look substantially faster than a stock M5.

Photo: Effective Execution 6

I like the appearance of the Vorsteiner wheels, but they aren’t the most practical. The tire valves are on the inside of the wheels, which makes them difficult to reach and leaves brake dust on your hands when you access them. The valves can also be blocked by the brake calipers if the wheels don’t land in the right position, and it’s easy to burn your fingers trying to check tire pressures between track sessions if the brakes are still hot. The spoked part of the wheels are also set slightly above the brushed aluminum lips, making it difficult to clean the brake dust that accumulates in those gaps. The wheels look great when clean, but living with them might be like having a high-maintenance girlfriend.

The TMS M5 might make life more difficult for one’s neighbors, too, because it sounds like a full-on race car on startup. It’s an awesome sound to car enthusiasts and I loved it, but I’m pretty sure those around me didn’t, especially before the car warmed up and the sound mellowed out. Even when it’s at operating temperature, the TMS exhaust is significantly louder than a stock M5’s, and it tends to drone a bit at certain engine speeds. But like Will Turner, I want to really hear a car, even if it’s a daily driver, and this exhaust would be at the top of my list if I were modifying an M5. My neighbors would just have to get used to it!

The increased sound suits the TMS M5’s amped-up performance perfectly. With around 600 hp at the rear wheels, this M5 feels supercar-fast, with midrange punch to two rival the Porsche 911 Turbo S or Nissan GT-R. Though that’s where it seems to have made the biggest gains, the TMS M5 feels substantially more powerful than the stock M5 at any engine speed, including above 6,000 rpm.

Frankly, there aren’t too many places where you can really get a sense of its speed outside of a long racetrack. I had access to a closed course of sorts, and the speed with which it reached 150 mph was impressive. Throttle response is improved along with acceleration, as is shift speed thanks to race transmission software for the M-DCT transmission. (The latter is still under development at TMS.)

Photo: Effective Execution 7

Recapturing the raw

character of the original M5

Of course, big power isn’t much good without handling, and the TMS M5 improves mightily on the stock M5 in that regard. With the lower ride height and stiffer springs as well as wider rubber, the TMS M5 feels sharper and more responsive, with less body roll in transitions and less front-end dive under hard braking.

The stock M5 is perfectly capable of taking on a twisty road, but the TMS car felt a lot more comfortable doing so at higher speeds. With all its extra torque, it’s great fun to power this car out of corners with the tires putting down big-time grip and the roar of the exhaust bouncing off the trees. The steering feel also seemed to be slightly improved, though it’s hard to tell without driving this car back to back with a stock M5.

Even with the handling upgrades, the TMS M5 remains comfortable for hours on the interstate or as a daily driver. The ride is definitely firmer with the H&R springs—this car has been tuned for better handling rather than comfort—but it’s not harsh or uncomfortable. Of course, the ride quality could also be further improved by fitting tires with taller sidewalls.

The best-executed tuner cars, in my opinion, retain the essential character of the originals while accentuating performance and thrilling their drivers in ways that the stock car can’t. The TMS M5 is significantly faster, handles better, sounds better and has a lot more street presence while remaining comfortable enough to drive every day. In an era when the bigger M cars in particular are becoming increasingly luxurious and more isolated from the road, TMS has also managed to recapture a bit of the raw performance characteristic of earlier M5s like the E28 original. Beyond the improvement in performance and looks, that may be TMS’ biggest achievement.

Also from Issue 129

  • 2014 i8 road trip
  • M Performance Parts F30 335i
  • Interview: Hildegard Wortmann
  • Buyer’s Guide: CPO BMWs vs. New
  • SLEK Carbon E85 Z4 M Coupe
  • Chase Donnelly's E46 328Ci
  • Cody Crochet's 1995 E36 M3
  • Barry & Lynn Friesen’s Türkis 2002 tii
  • Interview: Dr. Thomas Girst
  • Paddock Pass
Like Bimmer on Facebook   Facebook icon