Ford Focus ST Gets Boosted with ATP GTX28 Turbocharger

Sometimes our Project Cars are like boomerangs.  We sell them, and they come back for more.  Our VF Supercharged BMW M3 came back for KW coilovers and Status Racing seats.  Our Porsche 997.2 Turbo S came back for some carbon goodies and others which have gone far away out of country or state have ordered up new toys to keep them fresh.  So with barely a butt print in the factory Recaro seats of our Ford Focus ST, when we sold it earlier this summer, it was gone to the Northwest to a new home.  But that was short lived as the new owner wanted more power.  With every bolt-on done to the Focus ST from Agency Power, the next big step would be with the turbocharger.  After doing his research, the owner decided to go with ATP’s bolt on GTX28 turbocharger.  A ball bearing Garrett based turbo, its internal wastegate setup would not require a change of engine internals, fuel components, or anything else drastic to bolt it on.  So this was the plan to take her over 300 wheel horsepower which was nearly 400 at the crank.

With a the additional horsepower and torque, the front wheel drive car would have some serious traction issues.  In addition, the excess torque would definitely wear down that factory clutch making delivering the power to the wheels that much more difficult.  To combat and improve this, we went with 2 new products to help with the power delivery.  To help eliminate torque steer from the FWD, we added a Quaife LSD.  Instead of a 1 tire rubber burner seesawing at the steering wheel, the Quaife 1.5 way LSD helped deliver the power to the wheels equally to allow for more smooth control on launch and powering through the turns.  Working with the Quaife LSD was a stronger clutch and lighter flywheel.  With most of our builds, we went with a Clutch Masters clutch upgrade.  Their new FX250 is a great clutch unit to hold the access power while offering easy driveability from the full face disk.  Using a material called Fiber Tough on the flywheel side, it is less abrasive then kevlar yet just as strong.  Speaking of the flywheel, we went with Clutch Masters steel lightweight flywheel in place of the dual mass to help the engine rev out quicker and reduce turbo lag.

The final piece to the puzzle was with the tuning.  Others had installed this bolt-on turbo and just used Cobb’s Accessport Stage 3 map to get about 300 wheel horsepower.  But to take it a step further, we did a custom ECU Tune with our VR Tuned OBDII flash system.  VR Tuned has the ability to flash the Focus ST ECU via the OBDII port with its iFlash program.  We read out the data and have our tuner go through the mapping and adjust it accordingly.  After providing logs and dyno data, we can then further fine tune it to get the best ECU tune possible for the modifications.  Our tuning partner has been doing ECU calibrations for 13+ years in Europe and has had the ability to work with the EcoBoost engines and even previous Ford RS rally cars.

At Vivid Racing here in Arizona, we use a Mustang all wheel drive dyno.  At the time of the test, ambient temperatures were about 100F and we also run 91 octane.  Because of the heat factor, we did mix a liter of octane booster to bump us up to 93 octane.  Even though this is a FWD car, we chose to run it in AWD mode to give it a real world scenario and avoid any potential computer faults and failures from having only the front wheels spinning.  When the car came in, we did an immediate baseline with fresh calibrations.  The car with all the bolt-ons and a Cobb Stage 3 91 octane did 232 awhp and 299 ft/lbs of torque.  We then did our own VR Tuned ECU Flash on it to compare to the Cobb Accessport and was about the same with 234 awhp and 309 ft/lbs of torque.  Now with our baseline numbers and 4 days of work, we were able to tune the car and dyno it with the new turbocharger from ATP.  The car made MASSIVE amounts of power and torque over the stock turbo.  From 3700 rpm and on power was made with peak power at 5700 rpm of 70 whp.  Torque stayed at a consistant gain of about 65 ft/lbs from 4500 rpm to redline.  We actually had 1 more revision to this tune done to give the car a bit more boost and take care of the fall off at the top end RPM.  However we ran out of time and the owner had to hit the road.  With this revision we guestimate at about 315 awhp at peak redline.  Since this was run in all wheel drive, our Mustang Dyno is typically at a 20-25% drivetrain loss.  This puts us at about 400bhp or a complete gain of 150bhp over a stock Ford Focus ST.

Check out the install pictures, dyno, and video.  Please leave your comments!