Fully Developing an E46 M3

“I grew up watching Formula 1 with my dad in Brazil, so when I moved to the U.S., I wanted to enjoy everything this amazing country has to offer — including motorsport. After many years of hard work, I had built a good life for my family, so I started thinking about my other passions.”

Then in his late 30s, NASA Northeast racer Luiz Serva purchased a C55 AMG and began honing his new craft. By the time the bug had well and truly bitten, he was visiting Lime Rock Park as much as three times a week.

Eager to improve and expand his racing horizons, he got his racing license through a three-day Skip Barber course and started seeking a platform that would support his ambition.

His Road to Damascus moment came after a generous friend threw him the keys to his GTS3 E36 — and Serva got to taste what a focused racing car could provide. The Bimmer’s chassis balance, sound, and tactility were leaps and bounds beyond what the big Benz offered.

Within a couple weeks, Serva made the decision to take the plunge and join the talented drivers and builders in NASA Northeast German Touring Series. Though he’s not the tech-obsessed type, he appreciated the way the class welcomed innovation. In actual fact, it was the caliber of competition in the Northeast and the ways that would help him evolve which swayed him.

Class picked, he bought an E36 and immediately sent it off to Hi Speed Motorsports. They would have plenty of fun fine-tuning the machine in the near-future, but Serva was still relatively green and more than satisfied with the capabilities of OEM equipment. Factory brakes and driveline were sufficient for the modest power aim and 245-section R7s over five formative years, but after consulting his hero Randy Pobst on a better platform, Serva made the decision to upgrade to the E46, mainly for its wider track.

With this car, Serva and Hi Speed’s Hugh Stewart had plans to go much further. For handling, they added Hi Speed’s roll center correction kit, a set of MCS three-ways, a Cusco 1.5-way differential, and 275-section R7s. These parts, plus a few that came from Stewart’s own GTS3 machine, gave the eager-to-learn Serva a platform that would help him push past his known boundaries.

In search of more and more cornering speed, Serva decided to widen the footprint. Hi Speed fitted a fiberglass widebody kit to house a set of 315-section A7s. Being first on the scene with so much rubber stuffed under his fenders, a few competitors complained after Serva dominated the first race of the year. Three other entrants followed suit the following race weekend, and soon the 315-square setup became common.

It’s one thing to bolt on a set of bigger tires, but getting the most from them takes faith. Fortunately, Serva has a daring nature and a supportive friend in Stewart, who was happy to play the hare to chase. Stewart’s GTS3 car has been built to a similar standard, so any lead-follow laps could prove conclusively when Serva was not pushing hard enough.

He’s the type to eschew much dry analysis, preferring instead to rely on the sensations coming through the car. This approach has helped his improvisational skills and, crucially, learn to appreciate discomfort.

Into the Unknown

“You have to go past your known marks and find the new limits of the car,” said Stewart, who helped Serva find faith in the machinery, telling him simply that the only way to proceed was to “trust the new package and go.”

If the five tracks in his vicinity and the growing mechanical grip weren’t challenging enough, the rapidly evolving aero package gave him additional opportunities to challenge himself. An APR rear wing and plywood splitter were quickly replaced with a broader Klaus wing, an AJ Hartman diffuser, and a larger plywood splitter with fiberglass tunnels and Hi-Speed Motorsports’ distinctive shark fin stretching from the c-pillar to the rear wing.

Because this 3,100-pound middleweight only makes a moderate 305 horsepower at the wheels,  straight-line speeds haven’t been too high. Therefore, the overall brake wear has been manageable enough to retain the factory calipers — as well as the less-desirable Bosch Mk40 ABS. With Hawk Performance DTC-70 pads, which Serva finds easy to modulate, he can brake late enough when necessary and release the middle pedal correctly and consistently enough to find a real advantage in corner entry.

VIDEO

However, it’s the lack of necessary braking that sets this car apart. With an accurate front end, the car is a force to be reckoned with in long, high-speed corners where minimal deceleration beforehand pays dividends. “At NJMP Lightning, I don’t have to brake for Turns 2 through 6. This is where I go ten-tenths the first few laps, build a gap, and then I can reduce the pace a little.”

The typical downside to such a positive front end is a nervous rear, but the two have worked hard to find the stability needed to push 10/10ths at the drop of the green. Stewart’s M.O. of soft springs, soft packers, and stiff bars help provide compliance while keeping the aero platform constant in longer corners.

The damper settings and bump rubbers prevent too much dive under braking. The roll center adjustment kit, another Hi Speed product, improves the camber curve and keeps Serva on the intended line.

Softer springs help Serva over bumps, obviously, but it also helps him explore more of the curbing and other potentially unsettling parts of the track. Last month, Serva set a new record at New Jersey Motorsports Park’s Thunderbolt configuration, where compliance played a significant part. “Some people were asking me if the bump at T1 upset my car. I asked them ‘What bump?’”

VIDEO

The package has proven itself as one of the dominant forces in Northeast, currently owning all the GTS3 records along the Northeast circuit with one exception: Watkins Glen.

GTS3 speeds there were measured at the top of the esses, where Serva was clocked at a paltry 136 mph — 12 mph slower than his rivals. “It just stalls at 136,” said Serva. Despite that, he still set the fastest lap that weekend.

How? Minimum speeds make the difference, even at a fast, flowing track like Watkins Glen. Serva’s speed in the Bus Stop was a remarkable 112 mph — 7 mph faster than the next fastest drivers.

Drag Duty

Serva studied the aero package of cars from the Stock Car class in his home country and noticed how their front tires were hidden completely behind bodywork. His own slicks protruded ever so slightly, so when they devised a pair of fairings to cover the outermost edges of his tires, they saw an improvement of 1-2 mph at the end of the notable straights.

Though mostly insignificant in the grand scheme, this minor improvement started Serva and Stewart down the path of minimizing drag. Then came the removal of the dive planes with more encouraging results, and the two went back to the drawing board.

Serva and Stewart have decided to start fresh. The second iteration of the car will use the same powertrain, brakes, and top-side aerodynamic elements, but with a new body that will address the current car’s shortcomings in drag, weight, and underbody downforce.

This time around, the standard M3 body panels will be English-wheeled to accommodate the same axle width while minimizing the frontal area. A new DOM cage with different pickup points will enhance rigidity. Varying tube diameters and wall thickness, smaller gussets, as well as cutting away even more factory sheet metal should reduce weight by as much as 100 pounds, though only some of those pounds will be removed from the overall weight. The main aim of this diet is the ability to shift ballast more easily.

But the main improvements in grip will be made to the underside of the car, as these underbody elements are, generally speaking, less draggy than the aero elements mounted atop the car. Stewart will devise a new splitter with larger tunnels to feed a flat underbody of his own construction. They hope to construct this underbody with cost-conscious materials like aluminum, and rather than build a custom diffuser, update the current AJ Hartman diffuser. Whatever money saving will be put toward package optimization through wind tunnel testing.

Though the two have been in lock-step about setup so far, they currently have one point of contention. This revolves around tire width. Stewart, a proponent of 295s, argues they’re lighter, produce less drag, and sit a little shorter, so the net benefit outweighs the whatever additional grip the 315s produce. Serva jumped from the 275s straight to 315s, but feels so comfortable running them that he doesn’t have the desire to try the 295s.

The relaxed ruleset established the scope of this project, and their trust in one another took the car to the extent to which it sits today. “I’m up for anything he suggests. I enjoy this freedom and never think the car is good enough — I always want to make it better, and he does, too,” Serva said.

It’s their rapport, however, that’s given Serva supreme confidence in his machinery. “[Stewart] is my brother from another mother, and I just trust his expertise — especially when it comes to suspension setup. I never question his decisions!”

Stewart, too, believes in his colleague and friend. He knows Serva’s handling preferences and has learned to recognize when his driver is willing to go and push the envelope. “I no longer question him — if he says he’s going to go two seconds faster, then he probably will,” Stewart said with a chuckle.

Sounds like the ideal working relationship.