If you ever wondered what tuners would do once they got their hands on a McLaren MP4-12C, you aren't alone. For starters, 592 hp seemed restrained for an engine that, even at a small-ish 3.8 liters, made its power with the help of two turbines. And manufacturers play it safe with boost, leaving a lot on the table, so tuners use that advantage to make healthy gains with rewritten maps.
The first tuning mods for the 12C came in the form of plug-and-play piggyback modules that increased boost and fueling to match. Evolution Motorsports (EVOMS) of Tempe, Arizona, released its EVOMSit Intelligent Engine Control Module in September 2012. Good for 659 hp in Stage One form, this is a 43hp increase over the standard 616 (this car had the factory power upgrade).
Stage Two, which includes high-flow cats, brought power up to 701 hp (measured at the crank) with boost increasing from 2.5 psi to 2.94. But Todd Zuccone, founder and president of EVOMS, wanted to get into the ECU for greater control, not only of boost, but also functions such as ignition and fuel settings, launch control, and rev limiting.
Naturally, McLaren didn't want anyone gaining access to the 12C's brain. This is a company that builds some of the most technologically advanced racing cars in the world and supplied every Formula One team with a standardized ECU a few years ago. Zuccone said McLaren's ECU has a TP10 level of tuning protection, similar to some Mercedes-Benz, VAG, and BMWs he's worked on, and close to TP12—the highest level of protection he's seen to date. Not intimidated, Zuccone said there's always a way in, because "the OEMs need to be able to update software as per OBDII guidelines. This means ECUs will always have a way to be upgraded. It's just a matter of figuring out how."
Zuccone admits he's had some help. In the beginning, he sent out the ECU to have it unlocked. But now everything can be done in-house and he can rewrite an ECU within an hour. The maps in the 12C's Bosch MED17, he said, were similar to two Bosch maps he's previously worked on, so changing things was a mix of the somewhat familiar, plus a bit of trial and error.
Access to the ECU allowed Evolution to change its focus to the engine's limitations, mainly the two TD04 Mitsubishi turbos. They're small, quick-spool units that max out at 37 pounds of air per minute and top out around the 700hp limit of the EVOMS Stage Two module. Bolting on a bigger pair of turbos is next to impossible because the stock turbos fit so tightly in the engine bay, essentially maxed out as far as housing size is concerned.
The crew removed them and had the housings machined to accept a new ball bearing centersection, along with larger compressor and turbine wheels. After these modifications, the new turbo flows 49 pounds of air per minute, which allowed Zuccone to turn things up a few notches and get the engine to measure close to 700 whp on Evolution's Mustang 500 SE four-wheel dyno, burning 94-octane fuel. Assuming drivetrain losses are around 20 percent, that works out to 825 hp or so to the crank, hence the name of this package: EVT825.
Because the internals on this package are stock, Zuccone said he made sure to keep the torque (655 lb-ft) low to preserve the engine. He did so by gradually increasing boost for a flatter torque curve instead of pouring on the boost as soon as possible. Peak boost was raised from the stock 18 psi to 22 psi. An engine with stronger rods and pistons that can withstand even more boost is currently in development. The target is to exceed 900 hp. Other components include a set of NGK spark plugs, a couple of 200-cell high-flow cats, plus stainless steel exhaust pipes that end in a pair of black dual tips.
Some reviews of the MP4-12C complain that it lacks an intangible something that some might call "character." Especially when compared to its nearest rival, the Ferrari 458 Italia. "Too much British reserve," they said, "a bit cold and clinical." Maybe all it needed was an exhaust that doesn't have to meet sound regulations, because the system here hits all the right notes. This straight-through, X-pipe setup bypasses the mufflers to produce a gritty, metallic range of tones that gives it a racy—and characterful—edge.
Because I haven't driven a stock MP4-12C, I can't compare the two. But judged on its own, the EVT825 upgrade doesn't lack for low-end grunt. Playing it cool around town, the torque nudges the car along from as low as 1,500 rpm. These modified turbos spool up faster than the stock units, thanks to a more efficient vane design on both the compressor and the turbine side, so there's little to no trade-off in driveability found with other bigger-turbo upgrades.
Dig a little deeper to let the revs build and things get serious in a hurry. A swell of mid-range torque compresses the rear end's H&R springs and stock rear dampers as a warning that the horizon is approaching faster than the eyes can focus. Power builds progressively, continually building toward redline, and it never feels like it's running out of breath. Pull back on the paddle shifter through a few more gears, and triple digits arrive in no time.
Evolution claims to have shaved more than a second off the 60-to-130-mph time, the benchmark adopted by most tuners. According to Zuccone, the stock car posted 6.83 seconds with an altitude density of approximately 300 feet above sea level. The best time with the EVT825 package was 5.97 seconds with an altitude density of 2,300 feet. "With an altitude density similar to the stock run," Zuccone said, "that 5.97 seconds would be closer to 5.47 seconds. Or about 13 car lengths in a side-by-side race."
Part of the test route weaved through the mountains east of Phoenix where the 12C felt like it was always on the brink of exploding with acceleration. But those conditions also put the spotlight on the handling, which is nothing short of phenomenal. The front end feels light and the steering is almost telepathic. It turns in like a small, open-wheel racer and gives great feedback through the steering wheel. There's no wasted motion and the car never feels out of shape or unable to cope.
Evolution fitted exclusive ADV.1 ADV5.2 Competition Spec three-piece wheels. At 22 pounds up front and 24.5 pounds at the rear, this knocks off 5 and 4 pounds, respectively. They're wearing Toyo Proxes R888 tires, and the stock springs have been replaced by H&Rs for a slightly lowered stance. With its lower center of gravity and stickier shoes, working up to the lofty limits of this modified 12C is as much an act of bravery as it is of skill.