Faster, Cooler, Better: Bolt-On Upgrading the S550 Mustang GT for Street & Track Supremacy

• November 23, 2020
• Story By
  Mike Garrett

It was just less than one year ago that I purchased my 2016 Ford Mustang GT and in that time I’ve gotten to know the car quite well. It’s quirks, it’s attributes, how it does at the drag strip and does in the corners.

And up until this fall I’d held back entirely on modifying the car, with one exception, a set of RTR Aero 7 wheels and Nitto NT555 G2 tires, which I fitted to the car in May.

It wasn’t that I didn’t plan on modifying it eventually, I just felt more comfortable learning the car in stock form first, and even more importantly, coming up with a plan of attack for how I wanted to upgrade it.

Balanced Upgrades

Fast forward to October and it was finally time for the car to to go under the knife. After getting in touch with our friends at Steeda and ST Suspensions I came up with a list of goals and parts that would help accomplish those goals.

With a car as popular as the S550 Mustang is, there are endless routes one can take when modifying one. Some people go for all-out speed at the drag strip, others build their cars to wow at car shows and others do full-on dedicated road course builds that don’t even see the street.

For my car, the key goal would be balance. Rather than sending all my effort in one area I’d sprinkle in a bit of everything, all bolt-on, and all priced in a way that would still keep my total investment significantly less expensive than a brand new GT, let alone a Shelby GT350.

After chatting with the seasoned Mustang veterans at Steeda and the suspension gurus at ST, we came up with a plan of attack that would dramatically improve my GT’s all around performance, fun factor and looks without taking away from its livability.

I’ll be doing a series of articled documenting these upgrades in greater detail but here’s a quick overview of the areas we’d be addressing:

Suspension

The S550 GT with the factory performance package is a solid handler out of the box, but there’s big room for improvement, particularly when it comes to body control, predictability and driver confidence.

Traction

We’ve all seen the Cars & Coffee videos. A tail happy Mustang can be a ton of fun when you want it to be, but excessive wheel spin and wheel hop are typically the enemy of the enthusiast. While the S550’s move to an independent rear suspension paid dividends in terms of handing and ride quality, it also introduced some new challenges which the aftermarket has jumped out to remedy.

Braking

I was fortunate enough to find a Performance Package car which includes six-piston Brembo front brakes which have proven themselves well even in hard track driving, but there’s plenty of room left when it comes to things like rotors and pads.

Power

I grew up driving cars that make my Mustangs’s factory-rated 435hp feel like a top fuel dragster, but the power gains you can get from simple bolt on upgrades and tunes are hard to resist. And then there’s the factory exhaust system which has a nice tone, but is rather quiet for a muscle car.

Aero & More

Then there are other things that help improve both appearance and performance, functional aero upgrades for example, and small, but crucial areas like the shifter on manual transmission-equipped car.

With my car seeing regular road use, as well as occasional track and autocross on weekends along with a few drag strip sessions planned we’d come up with game plan that should be make the car better and funner in all of those areas without taking away from the comfort and reliability that makes modern performance cars so great.

With an entire SUV-load full of parts finally in hand and ready to install it was time to get to work. And rather than installing each part individually I was fortunate enough to have another car to use for the daily grind for a few weeks.

That meant my dad and I were able to take our time on the project, putting the car in the garage for a few weeks, working a couple hours a day and never having to rush to get it back together.

For a daily driven car this often isn’t possible, but I can’t recommend this method enough if you have the ability. It made things so much easier and less stressful, as we have a decent amount of DIY experience but are by no means professional mechanics.

I’ll be back shortly to start going through the meat and potatoes of all the upgrades and how they’ve improved the car but this should give a nice overview of what our starting goal was.

Stay tuned for more next week.