Review: ISC Coilovers on a 2016 Fiesta ST, the On-Road Test

If you have read any automotive publication in the past couple of years, including this one, then you have seen someone waxing lyrically about how good the Fiesta ST is. Phrases like, “handles like a dream”, and “it is so much fun” get thrown around like rice at a wedding. With so much positive press out there, it can be easy to think that the Fiesta ST is a perfect vehicle; an enthusiasts dream. While it is the latter, my many articles on my planned and actual improvement modifications show that it is by no means perfect. One of the most glaring areas which needs improvements–at least on my low-quality California roads–is the suspension.

The Fiesta’s suspension in stock form is surprisingly capable, gently understeering if pushed too hard, with mild, controllable lift-off oversteer tucking the nose back in, making for a fun, enjoyable driving experience. Ford’s engineers were somewhat limited by the platform of the Fiesta, as the rear suspension consists of a solid twist-beam rear axle. However, since this isn’t the driven axle, this isn’t the performance detriment it may seem at first. As the front, driven wheels are independently sprung, the rear-axle is mostly just along for the ride, which means the simple rear-axle helps keep cost down. While capable–and most importantly, fun–the stock suspension is not what anyone would call comfortable. On California’s poorly maintained roads, the Fiesta’s ride is on the crappy side of bumpy. This is where I see the main area for improvement lies in any aftermarket suspension set-up for the Fiesta ST; controlling the bumpy ride, while giving better control of the car.

With that in mind, I set out looking for a suspension set-up for my Fiesta. While a simple spring over the OEM damper was tempting, I felt a more thorough job was required. When most people look towards coilovers, they think of bouncy rides, and bro’s justifying their low ride height with claims like, “it’s a track car for the street, bro. Live with it”. As my SRT8 Charger is already set-up on coilovers, comfortably, I knew this didn’t have to be the case. As I was looking for more of a ‘street-car for the track’ set-up on my Fiesta, I was determined to tame the bumpy ride of my stock car. In the pursuit of this goal, before I even changed my suspension, I went from 205/40/17 tires to 215/45/17 tires, not only giving me more of a contact patch, but also giving me a slightly more absorbing sidewall. While my Charger’s weight helps tame the ride quality of the coilover system it has, my light-as-air Fiesta did not have that going for it.

Now, it is important to note here that I am purposefully avoiding KW suspensions. While they are great– Charger has a V3 system–ey are also expensive, and are too quickly becoming the “go-to” answer for coilovers. Not only did I want to prove other companies can’ be discounted, I wanted to keep the budget-air of my Fiesta. After doing the usual forum and video browsing, I noticed that people who had ISC coilovers in their car generally had a fairly compliant ride. After contacting the company, they told me they had a normal Fiesta system developed, but not an ST specific variant. After a bit of back and forth, it was decided that we would try the Fiesta system on my ST and see how it went.

Purchasing was as simple as any online ordering system. Shipping took about a month, but this was because the US warehouse did not have any systems in stock–surprising considering the lack of modified normal Fiestas wandering the streets. Had it been in stock, shipping would have been as quick as three days. Despite this shipping, the wait was bearable, and soon enough my ISC coilover system was waiting for me on the doorstep.

Upon seeing it in person, I knew that the second reason for my choosing ISC–l of the ‘little bits’ they include–was well founded. ISC sells their systems as the “N1 package”, and it includes more than merely the coilover. Also included in all of their kits are upper mounts, thrust bearings, and camber plates–if your vehicle can utilize them. As I am not a suspension expert, I really appreciate a company that does all of the thinking for me, because frankly, I wouldn’t even know to shop for thrust bearings, upper mounts, and the like. Having them included gave me a certain peace of mind before the product was even on my car.

My already stated lack of suspension know-how means that I opted to wait for time at my local ISC partnered shop, S&N Motorsports in Elk Grove, California. This is the same shop where Mike Spaghetti gave away his M3, which is how I found out about them. There is always some cool stuff in the shop, such as the S/C Lincoln Blackwood that they were trying to revive when I dropped my car off. Installation was a snap, and while it would have been done in a day, some other work I had done necessitated them keeping it overnight. During installation, one hiccup did come up: there is no way to access the top of the damper for adjustment in the rear, once they are installed. This means adjustment is difficult, but as I was shopping for coilovers for the fine-tunability, rather than the quick-adjustment features, this did not really bother me. It did mean, however, that they had to be set and left alone, or taken out to be re-adjusted. My mechanic suggested that this could be fixed by moving the dampening adjustment to the side.

With that in mind, we decided to set the dampening right in the middle. ISC advertises 32-way adjustable, and from the sounds of it, it really is. In terms of ride height, I wanted a usable car, and so we kept the ride height relatively high, only dropping it about .5in over stock. Do not worry; it still passes the MCM shoe test. While there are some roads in California which can be called “adequate” the drive home from the shop was not one of those. The bumpy, pitted surface provided the perfect test for the ride quality. Sadly, I was wholly disappointed on the ride home: the bumpy ride was still there. Luckily there was no scraping, rubbing, or bottoming out, but it still wasn’t what I was looking for. I almost immediately called and scheduled an adjustment at S&N.

Taking it back, we decided to turn the dampening to 4 ticks above their softest setting, while leaving the ride height alone. Picking it up, I made a point to drive the same roads back home. While before these roads elicited disappointment, now they only brought smiles. As my lowered Fiesta glided over bumps smoother than the OEM suspension, taking corners flatter as well, I couldn’t help but smiling. I had recently listened to a podcast with Steve Dinan, of Dinan Tuning, and he mentioned that with modern tire technology, they are tuning their aftermarket suspension systems to be softer than OEM systems. This softness actually improves real-world performance in his view, and I couldn’t help but agree with him as I drove home. Taking bumps without a cringe or care, going over speed bumps and stupid, California-required sideway gutters without bottoming out vilifies the suspension for everyday use. Folding the seats down and stuffing the Fiesta full of my junk didn’t bother it at all either.

If it seems like I am focused on the comfort of these coilovers, rather than the performance, it is because I am in this review. Since taming the ride quality was a main consideration in my shopping, it is only fair that it is a main consideration in my review. Performance junkies, don’t worry though; I have you covered. The day after I finished tuning the suspension, I loaded up my supplies, drove a comfortable two hours out of my way, and attacked Thunderhill Raceway, thoroughly giving the suspension a working-over. Because of the convenient timing of the track day, the performance review of the suspension will be coming on Friday, in two days, with my time at Thunderhill as the focus. Stay tuned until then, and don’t forgot to like the article and share it with your friends. If you have any questions, leave a comment down below.

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