I realize it’s been quite a while since the last update on Project EcoBoost – my 2015 Ford Mustang daily driver. When we last talked about this, I’d just fitted a set of 20-inch RAYS Volk Racing TE37 Ultras and new Nitto tires – and then things went kind of quiet. The car actually sat in my garage for a whole month while I was working in Japan, and once I returned I was eager to continue with the modifications.

After first doing some basic power upgrades which I covered earlier this year, along with the aforementioned wheels, my next goal was to start tackling the suspension.

In comparison to the previous Mustang chassis, Ford did a fantastic job with the suspension and handling on the new S550 – thanks in large part to the move to an IRS setup. But there’s always room for improvement, right?

Actually, right after picking up the car one of the first things I did was reach out to our partners at KW to see what they might have in the works for the new Mustang. Early searches of the forums showed that many people were installing lowering springs to drop the ride height, but there was little in the way of full coilover kits available.

Not surprisingly, I found out that KW and its partners were indeed developing suspension parts for the new Mustang, but it would be some time before they were available. Quality is always worth the wait though, and as I was going to be out of the country for a while anyway, there were no complaints on my end.

Not long after I got back from Japan, I got word that Project EcoBoost’s coilovers were on the way and that they’d be one of the first production sets out there. My set would actually be Roush brand coilovers made by KW – the latest collaboration between the two companies. Given KW’s experience constructing high quality suspension setups and Roush’s expertise building wicked-fast Mustangs and kicking ass in motorsport, this seemed like a very solid combo.

I happen to live pretty close to KW’s massive new North American headquarters in Central California, so rather than fitting the parts in my cramped garage I asked if we could do the install at KW’s shiny new facility.

Not only is this place a distribution center for the KW products built at the main factory in Germany, it also includes local production and assembly, R&D, marketing and everything else you’d expect from one of the world’s top parts makers.

This is also the place that handles suspension development and maintenance for race teams across America – including many Formula Drift competitors. I was very impressed with what I saw.
On The Lift
Anyways, back to the car. I drove the Mustang into the roomy service bay where KW North America performs their measuring and prototyping.

The specific Roush coilovers I’d be using are the three-way adjustable models, but in addition to these KW will also be releasing its own coilover setups for the S550, so Mustang owners will soon have a lot more options when it comes fitting suspension upgrades.

Here’s an image of the stock front strut and spring setup next to the Roush coilover. Roush specced, the spring rates on this setup are perfect for weekend track days while still being totally comfortable for a daily driver – exactly what I was looking for.

After removing the front brake calipers and rotors, the front install was pretty straight forward. I was again reminded how nice it is working on a clean, new car rather than one covered in grime.

The rear install was slightly more involved, mainly because we loosened the rear subframe to get the factory springs out. All of this had me very glad that I didn’t try this install in my garage without a lift.

Here’s a shot of the new rear springs with their adjustable collars. As you can see, these things are heavy duty.

And a view of the stock rear shock next to the new Roush piece. The adjustment knob is located at the bottom for easy access.

With the subframe loosened, the rest of the install went smoothly. With a couple of KW’s finest handling the heavy lifting and me taking photos along the way, it took around three hours to get everything on.

Here’s a shot of the rear springs installed and ready to go just prior to refitting the wheels and putting the car back down on the ground.
Impressions
While the Roush coilovers are three-way adjustable, I decided to initially leave the damper and ride height settings to what they were out of the box. I was told the factory settings have a nice balance of performance and comfort and I was curious to see how they’d feel.

As for the initial ride height, the car was far from slammed at the original settings but they did a nice job of closing up the wheel gap the car had with TE37s and the stock suspension.

One of the things I like most about the S550 compared to the old S197 is the wider, lower stance the car has. Fitting the new coilovers has helped things get even better in this department.

Immediately after finishing up the install, I took the car in for a proper alignment and then hit the road to see how she felt.

The coilovers have only been in for a couple of weeks, and while I haven’t yet had the chance to hit the track or to really wind out on a mountain road, my initial impressions are quite positive.

The new Mustang had already left the previous versions in the dust when it came to control, but the new suspension along with the 275 Nittos on each corner has only made the car feel even more planted.

The car still rides very well too, and that’s important because comfort on long road trips is one of the big reasons I chose the Mustang over the FR-S I had prior.

Yes, it’s certainly a bit firmer than it was with the stock suspension, but unless you’ve felt the two setups back to back, I think it would be hard for most people to notice the difference.

And of course, if I do head for the race track or a day out in the canyons, I can use the adjustability to firm things up even more. For now though, I’m quite digging the balance.

I’ve had Project EcoBoost for six months now, and I couldn’t be happier with it. With the increased power, more aggressive noise, wicked set of wheels and added grip I think it does an even better job of being the affordable turbocharged sportscar we’d been hoping for.
What’s next for the car? Well, I’ve actually got a few odds and ends sitting in my garage that still need to be installed, so you can expect to hear about those soon. From there I’m thinking about moving to the exterior for some subtle upgrades. As with everything else I’ve done so far, it should be a lot of fun. Stay tuned for more Mustang adventures.
Mike Garrett
Instagram: japanifornia_media
mike@speedhunters.com