2015 Ford Focus ST

Welcome to my 2015 Focus ST build thread!

This page is dedicated to tracking the modification progression of my 2015 Focus ST (FoST) along with performance gains realized. The Focus ST is an amazing little car! It comes with the Ford EcoBoost 2.0 liter 4 cylinder direct injection turbo-charged engine. From the factory, this car puts out 252hp and 270 ft.lbs of torque. Keep in mind, these numbers are not at the wheels, but measured at the crank, so the actual wheel horsepower (whp) and wheel torque (wtq) will be less. My FoST came with the full Recaro seats, ST3 and 402a packages. The car is a perfect commuter to and from work and for longer trips due to the exceptional mpg-to-horsepower ratio! Although this 4 banger puts out some serious ponies and torque for its size, it does so extremely efficiently. Since I have had the FoST, I have not averaged below 20mpg on any tank! Typically, during normal conditions, commuting to and from work, i’ll average closer to 24mpg! On the highway, cruising, these numbers continue climbing closer to 30mpg! Simply amazing, in my opinion, for the amount of power it is capable of putting to the road. Speaking of power, let’s get to the mods!

Stock:

The car was originally purchased from Wade Ford without any mods, new vehicle. From there, before modifying anything, I wanted to get a solid baseline on the dyno to see exactly where the car was from a whp and wtq perspective. It came in @ 219.5 whp & 265.9 wtq on the best run.

Cobb Stage 3 Kit:

One of the main things I wanted to do to the car once I bought it was change out some of the basics, such as intake, exhaust and front-mount inter cooler (FMIC). The best setup I could find was the stage 3 kit by Cobb Tuning! This kit had it all, the full turbo-back exhaust with a catted down pipe, intake, FMIC w/ new charged air piping, rear motor mount (RMM) and last but certainly not least, the Cobb AccessPORT v3! In addition to the Cobb Stage 3, I also added the Turbosmart 50/50 blow off valve (BOV), Cobb symposer delete (which was a fancy little thing Ford added to channel intake air into the cabin to make the car sound more throaty. Cheesy, so it was blocked off in lieu of actually hearing the real engine!), and Cobb short-shift plate to reduce shifts by 40%. Cobb really does make top-notch products, perfect fitment and excellent quality, I could not be happier! After installing these components, I took the car back to the dyno for another run to see performance gains from the additions. At this point, from a tuning perspective, I just applied the Cobb OTS stage 3 93 octane tune that came with the AccessPORT. It came in @ 242.9 whp & a whopping 330.3 wtq on the best run. That is a gain of +11% whp and +24% wtq. Honestly, I was expecting more from the whp perspective; however, the wtq was off the charts! Going from 265 to 330 is a HUGE difference on the street!

Stratified E-85 Flash Tune:

Now that Cobb stage 3 has been installed, I wanted to look further into tuning as the OTS tune from Cobb still left a lot to be desired on the whp side of things. In addition, the OTS tunes have to run super conservative since they are “off the shelf” tunes that have to work & perform in a huge variety of conditions, gas quality & grades, altitudes, etc.. E-85, as you may know, is the fuel that can be used in the Flex Fuel capable vehicles. The FoST, although not designed to run on 100% E-85, can tolerate E-10 to E-15 all day long, it even says so right on the gas gap. By introducing a blend of E-85 along with high test 93 octane fuel, you achieve a mix closer to E-30, which has been proven to yield significant performance increases, especially in turbo-charged engines. By introducing the E-30 mixture, you are effectively increasing your octane level quite a bit beyond 93, allowing for higher boost and more aggressive tuning while still avoiding detonation. If you would like to learn more on the subject, please visit the forums and research. I now have applied the Stratified E-85 Flash Tune via the AccessPORT and have done the 3 gallons E-85 and topped it off with 93. This definitely added a good deal of pickup to the car, and the numbers proved it! Went from 242.9 whp & 330.3 wtq up to 261.9 whp & 349.5 wtq!

Modification List:

Cobb Intake
Cobb FMIC w/ Charged Pipes
Cobb RMM
Cobb Turbo-Back Exhaust
Cobb Exhaust Hanger Kit
Cobb Short-Shift Plate
Cobb Symposer Delete
Cobb AccessPORT v3
Cobb Shift Knob
Turbosmart 50/50 BOV
Boomba Racing Wing Risers
Mark II Shark Fin Antenna
JSTUNED (93 + E-85)

Pictures:

Stock