Putting more boost in EcoBoost
Our 2015 Ford Focus ST’s workout regimen begins with the Mountune MP275 engine kit that includes a new intercooler, new intake plumbing, and new engine computer programming. It increases the 2.0-liter turbo-four’s total output by 23 horsepower and 26 lb-ft of torque. While paying $1,900 for such a modest horsepower gain might sound like a bad deal compared to some other aftermarket tuners, Mountune notes that the larger intercooler included with this package is essential to making more power. Without it, representatives say, increasing boost would quickly heat-soak the Focus ST’s intake plumbing, meaning you’d only get extra horsepower for a few full-throttle runs.
Out on the road, the difference is noticeable the first time you plant your right foot. The tuned 2.0-liter engine makes more power than stock from idle all the way up to redline, pulling with much more urgency than the standard Focus ST. We detect zero surging or lagging from the turbocharger, just strong boost that’s available at a moment’s notice.
As we wring out the engine, we’re also savoring the Ford Performance short-shift kit fitted to this car. Unlike some aftermarket parts, it shortens the shift lever itself rather than a linkage at the transaxle. Translation: The shift knob sits lower in the center console, and throws between gears are notably shorter, heavier, and more direct than in a regular 2015 Ford Focus ST, without the notchiness of some short-shift kits. The new part gives the Focus ST’s already excellent six-speed manual a feeling of solidity and precision that makes you never want to go back to stock.
With a new catback exhaust from Ford Performance in the mix, this Focus ST even gets a mean soundtrack to match its added muscle. It burbles and snarls with far more aggression than the standard car, although not so loud as to muffle the whooshing and hissing of the turbocharger up front. When you’re off boost, the exhaust stays as quiet as a regular Focus ST, making this a practical and rewarding exhaust we could live with every day.
“These pipes make the car sound wonderful, packed with attitude and purpose,” agrees daily news editor Eric Weiner.
Sticking it to the pavement
Mountune includes a strut-tower brace and Ford Performance lowering springs, but the standard Focus ST is already so stiff that it’s tough to quantify any gains outside of slinging it around a racetrack. For spirited street driving, there is one Mountune upgrade that demonstrably cures one of the Focus ST’s famous flaws. Torque steer has always ailed the Focus ST, but the remedy is a Quaife limited-slip differential. It’s especially helpful at increasing traction to compensate for the added power and all-season tires of our test car. “That’s what this car always needed,” says videographer Sandon Voelker.
Weiner agrees: “If you abuse the throttle mid-corner, the differential takes it in stride and quells most of the unpredictable handling we know from the regular ST.”
At $1,174 before installation, the limited-slip differential is not a cheap upgrade, but it’s the one that makes the most noticeable difference in how the 2015 Ford Focus ST puts power to pavement. Especially if you’re upgrading the engine, this differential is a must-have component to tame the ST’s performance.
What’s the benefit?
Plenty of tuners offer similar tweaks for the Focus ST, so Ford knows it has to provide a unique selling point in terms of warranty coverage. Unlike aftermarket parts, all these components are covered by Ford’s standard warranty, meaning there will be no arguing at the dealership if something goes wrong after you install the upgrades. If you’re concerned about keeping your warranty and like knowing the parts were developed in-house, Mountune and Ford Performance can rejuvenate your Focus ST relationship without the risk.
Still a gem
However you slice it, this 2015 Ford Focus ST demonstrates the Blue Oval’s commitment to affordable performance. Few automakers offer dealer-installed go-fast parts, and we’re pleased Ford is catering to the needs of horsepower-crazy enthusiasts.
Most of all, though, this car reminds us how much we like driving the regular 2015 Ford Focus ST. The Ford Performance parts installed on this one don’t transform the hot hatch so much as emphasize its virtues and soften its flaws. In stock form or pumped up with aftermarket parts that won’t void your pre-nup, the Focus ST is a well-rounded performance car that keeps enthusiasts interested well after the honeymoon phase wears off.
2015 Ford Focus ST ST2 Specifications
|Price:||$31,890/$36,992 (base/as-tested, est)|
|Engine:||2.0L DOHC 16-valve turbo I-4/275 hp @ N/A rpm, 296 lb-ft @ N/A rpm|
|Layout:||4-door, 5-passenger, front-engine, FWD hatchback|
|EPA Mileage:||23/32 mpg (city/hwy)|
|Suspension:||Strut-type, coil springs/multilink, coil springs|
|Tires:||235/40/ZR18 Pirelli P Zero Nero A/S|
|L x W x H:||171.7 x 71.8 x 58.4 in|
|Headroom (F/R):||39.1/37.9 in|
|Legroom (F/R):||43.1/33.4 in|
|Shoulder Room (F/R):||55.6/52.6 in|
|Cargo Room:||23.3/44.8 cu ft (seats up/down)|
|Weight Dist. F/R:||60/40|
|0-60 MPH:||5.7 sec|
|¼ mile:||14.7 sec @ 96 mph (est)|
|Top Speed:||154 mph|