HGMS Mustang Mods Go Sinister on GT or EcoBoost

At HG Performance we are very fond of the newest Ford Mustang, the 2015+ S550 Mustang. As far as Mustang mods go, we’ve had the opportunity to work on a good number of them, from the 5.0-liter GT to the turbo 4-cylinder Mustang Ecoboost.

The new S550 Mustang is a great car in more ways than one. When looking at both a V8 Mustang and a 4-cylinder EcoBoost Mustang, you realize that the approach to Mustang mods can be quite different.


Featured Mustangs


These two Mustangs might look like twins in their color scheme of grey on black, but they couldn’t be more different.

For most cars, exhaust is almost always an important early upgrade. The case is no different with these two cars. Flow is important but so is sound. In a list of Mustang mods, it’s hard to expect anything less than an exhaust upgrade first, whether its 4 or 8 cylinder and whether or not it happens at the beginning or end of the build. The exhaust is always in mind somehow. The thought of it is always there as the icing on the cake for how the overall package is going to sound… with the added benefit of better flow and more power.

The story goes like this: The one Mustang – the 5.0 V8, is running a Corsa Extreme Catback. The Ecoboost Mustang is using a Ford Racing Catback by Borla Exhaust. The Ecoboost’s sound and power is also enhanced by a Stainless Works Downpipe. The V8 of course doesn’t have one of those as it’s naturally aspirated.


The 2015 Ecoboost Mustang

2015 Ford Mustang EcoBoost


In an unsurprising fashion, the Mustang mods to the EcoBoost car revolve heavily around extracting more power from the turbo 4-cylinder. This is typical of any turbo 4 build. WRX/STI, Evo and Ford ST fans will of course understand this perfectly as it’s the standard for those platforms.

However, while the S550 4-cylinder EcoBoost Mustang is not the first turbo Mustang ever created, it is the one that pioneers turbo Mustangs in the era of readily available ECU tuning solutions. While tuning itself might seem like black magic to some, acquiring a good system for tuning or a tuning wizard to make it happen no longer are. This is new ground for Mustang modding however. Turbo 4 fans jumping ship from other platforms to the new turbo pony might feel right at home. Only now they’ll have rear-wheel drive rather than the more common FWD or AWD of turbo 4 platforms. But, for the traditionalist Mustang owner of the V8 variety trying EcoBoost for the time, this is fresh new ground.


EcoBoost Mustang Mods


To coax more power out of the Ford EcoBoost engine, we’ve used one of the world’s leading experts in turbo tuning technology to provide the interface, COBB Tuning. We’ve used a COBB Tuning Accessport V3 for Ecoboost Mustang as the tuning system and then using our in-house DynoDynamics dynamometer, Delicious Tuning came up with a sweet custom tune for the car.

The custom tune is almost a necessity when picking and choosing upgrade parts from various manufacturers, as is the case with this car. Sticking with a single system is great and can save you some money while also allowing the ease of an off-the-shelf map. However, for the ultimate in personalizing, you cherry pick the parts you want from various manufacturers and then have a wizard come in to orchestrate their implementation using the COBB Accessport as the interface. Thanks to our in-house dyno and our close relationships with some of the best tuners around, this is the ideal solution, albeit more costly. It worked wonders on this EcoBoost Mustang though.

To round things out, this EcoBoost Mustang has an Airaid Intake and a FullRace FReak-o-boost front mount intercooler with charge piping. The downpipe, exhaust, intake and intercooler all work together with the new custom tune to dish out the newfound horsepower and torque.

Given the main goal was more power… Here’s the dynograph to prove the gains. (WHP Dynojet conversion from DynoDynamics)


2015 S550 Mustang EcoBoost Wheel Horsepower Dynograph


For suspension, it’s running an Eibach Pro-Kit combo of springs and sways. The matte black color scheme of the wheels is achieved with a set of 20” HRE FlowForm FF01 wheels in Tarmac wrapped in Pirelli PZero 265/30R20 at the front and 285/35/R20 at the back. The spec of the FlowForm FF01 for S550 Mustangs is 20″ FF01 20×9.5 et35 front and 20×10.5 et45 rear.


The V8. 2015 Ford Mustang GT

Mustang Mods HRE FlowForm FF15


Unlike the EcoBoost Mustang, this GT acknowledges the fact that it’s already a very powerful car. After the addition of the Corsa Xtreme Catback exhaust, the modifications revolve around drivability.

The car is also lowered on Eibach ProKit Springs. Then it gets BMR adjustable sway bars with adjustable end-links. More BMR parts include: Cradle bushing lockout kit and vertical links with spherical ends.

Additionally, the car has Bob’s Ultimate Oil Separator to help clean up intake air. This is to remove oil from blow-by that will otherwise end up in the intake system, mucking it up, reducing fuel octane and robbing horsepower.

To round out the drivability package this S550 5.0 has a Steeda transmission insert bushing and a Steeda Heel and Toe pedal for… you guessed it, improved heel and toeing.

Let’s not forget the matte gems in this sinister-looking package… The HRE FlowForm FF15 wheels in Tarmac (matte black). The spec on those are 20×10 et40 front, 20×11 et55 rear. Their multi-spoke design looks absolutely brilliant on the new Mustang. Tires are Vredestein Ultrac Vorti R 265/35/R20 front and 305/30/R20 rear.

Here is the dynograph for the Mustang GT V8 after adding the exhaust. Again, these are Dynojet conversion numbers from DynoDynamics. Notice the gains from just the catback alone!


S550 2015 Mustang GT Dynograph After Catback


Like we said, at HGMS we love the S550 Mustang. Whether it’s the EcoBoost 4-Cylinder Turbo Mustang, the tried and true V6 Mustang with the newer style more powerful engine that debuted in 2011 or the blueprint 5.0 Mustang, we have the expertise to work on your car. We can make recommendations on Mustangs mods, install what you prefer and test and tune on our in-house dyno. Everyone knows the Ford Mustang is nothing but a blank canvas for developing your ultimate pony car. At HG Performance we help you build the Mustang of your dreams, whichever the flavor you pick.

For reference, here is a list of the mods on these two featured Mustangs:


2015 S550 Mustang EcoBoost

  • Stainless Works Downpipe
  • Ford Racing by Borla catback exhaust
  • Airaid Intake
  • FullRace Freak-o-boost front mount intercooler
  • Cobb Accessport v3
  • Custom dyno tune by HG Performance
  • Eibach pro-kit suspension (springs/swaybars)
  • 20 “HRE FF01 20×9.5 et35 front and 20×10.5 et45 rear
  • Pirelli Pzero 265/30R20 front and 285/35/R20 back


2015 Ford Mustang GT

  • Corsa Xtreme catback
  • Eibach ProKit springs
  • BMR adjustable sway bars with BMR adjustable end-links
  • BMR cradle bushing lock out kit
  • BMR vertical links with spherical ends
  • HRE FF15 20×10 et40 front, 20×11 et55 rear in Tarmac
  • Vredestein Ultrac Vorti R tires: 265/35R20 front and 305/30R20 rear
  • Bob’s Ultimate Oil Separator
  • Steeda Transmission insert bushing
  • Steeda Heal/Toe pedal


Finally, for good fun, check out the comparison of both cars on the same dynograph. This shows you how the Ecoboost and the GT compare after the Mustang mods on both. Of course, there are infinite ways this chart could look like depending on what mods you choose, your budget, etc… but this should give you a pretty good idea of a great starting point for your own goals. It might even help you decide which car to buy if you are unsure on which engine you want. Reach out to HG Performance today to find out what mod options we can provide for your Mustang.


Modded 2015 EcoBoost Mustang vs Mustang GT