Upon buying my S4, the first thing I knew I wanted to upgrade was the suspension – the stock suspension (even with the so-called sport shocks & springs) was very spongy and sloppy. I knew I wanted a coilover setup versus a spring and shock setup as I think the full coilover setup works well together, often rides better, and most importantly coilovers give me adjustability to make sure everything is dialed in EXACTLY how I want it. While some spring & shock combos can be good, I knew that if it weren’t perfect it would eventually drive me nuts and I’d end up buying coilovers in the long run anyway.
The Coilovers I Considered
I reviewed all of the options and narrowed down my list to STaSIS Motorsports, STaSIS Ohlins SL (now named the STaSIS Challenge), KW V3s and Bilstein PSS9s. On my A4 I ran the base Koni Coilovers, and while they were a perfectly decent setup, they were much too soft for track duty and sometimes even too soft for daily driving duty. Following the “do it once and do it right” mantra, my initial feeling was to go for the STaSIS Motorsport setup; however, the $3800 price tag was just too big of a pill to swallow. I began researching and talking to many people, and while I received nothing but glowing feedback for the Motorsports, I also heard from a number of people that they rarely adjusted the dampening and tended to treat them much like the Ohlins SLs – set it and forget it. Eventually I ruled out the Motorsports (even though I really wanted them) as I just couldn’t justify the cost, even if I were going to track the car. This narrowed down the field to three choices; ultimately I decided to go for the STaSIS Ohlins SL both because of STaSIS’ stellar reputation as well as the undeniable quality of Ohlins dampers. While the PSS9s appealed on the basis that its very easy to adjust dampening (much like the Motorsports), I’ve heard mixed reviews on them in both track & street scenarios and just wasn’t sure if I’d truly be happy with them. I also happened to come along a set of very lightly used Ohlins SLs at a price I couldn’t say no to, so alas my decision was made.
Swift Metric Spring Upgrade
Upon consulting some friends with both Motorsport & Ohlins SL setups, I decided to upgrade the springs from the Eibach springs that STaSIS supplies to a slightly stiffer setup from Swift. I purchased the Swift Metric series springs with a 784 lbs front spring rate (Eibachs were 700 F) and a 1232 rear spring rate (Eibachs were 1100). More importantly the Swift springs use a special metallurgy that offers better performance using less unsprung weight (read up on the technical stuff here). As I saved a lot of money buying a used setup, I figured the $370 I spent on the Swift Springs upgrade was prudent to make sure I was blown away with the end result – and indeed I was. In hindsight, I think these spring rates were a bit too aggressive for a daily driver, and I’d recommend sticking with the STaSIS spring rates of 700f 1100r for a more street oriented setup, or 750/1200 for a more performance oriented setup.
Track Testing & Review
Literally three days after getting my Ohlins SLs installed and the car re-aligned, I took her to the track to get a real understanding of the limits of the suspension. A group of friends and I drove from Phoenix to Las Vegas (approximately 300 miles right there) and then visited Spring Mountain Motorsport Ranch for a day full of testing & tuning. As you may know, I’m no stranger to the track, as I race in the 24 Hours of LeMons with Audi Style Racing in an 80’s Audi Coupe GT, and had also taken my A4 to several tracks throughout Arizona and California. The track was phenomenal, with a nice variety of turns and challenges including two nice and long constant radius turns up front and some challenging chicanes in the back (we did the North-South configuration for those familiar. I went with my friends at Four Rings Racers Group (FRRG) and we had everything from a TTRS to a used Audi A6 out there shredding up the turns. I’m not a professional race car driver by any means, but I guess I do feel somewhat qualified to give this review.
One word: solid
Another word: wow
The car was super smooth and body roll was virtually non-existent. These are night and day from my entry level Koni coilovers I had on my A4. The car felt very neutral – while some understeer remained, I also found that on certain carousels I could get a little oversteer if I pushed hard enough, which was quite fun. The car was VERY predictable and took very little time to neutralize after hard cornering. There were several chicanes were you had just a split second to stabilize the car before embarking on the next turn, yet no matter how hard I pushed the car could be quickly stabilized and be poised to attack the next corner. The video I took demonstrates just how stable the car is – inside the car, it feels even better. The confidence and predictability the STaSIS setup gave me allowed me to feel the real potential of my car and focus on my driving and lines without having to worry about how the car would handle or if I were pushing the suspension too far. Unrelatedly, I was suprised how well the rest of the car held up too – despite being on stock brakes and stock tires, I found the tires (Michelin Pilot Sport PS2s) to be very grippy and last a long longer than I expected, and I kept expecting the brakes to fade or give out altogether but shockingly they held in too. Occasionally I did feel brake fade, but after taking a momentum lap they’d pretty much return to ready-mode. That being said, brakes are definitely the next upgrade I want (while power adders would be fun, I’d rather use the current power to its potential first).
Street Driving Impressions
Along with my track day fun came a 600+ mile round trip to and from Vegas. I’ve also been commuting to work on a regular basis, so I feel I’ve got a solid understanding of the street characteristics of these coilovers after nearly one thousand miles of seat time with them. If the street comfort level were a 8/10 from the OEM setup, I’d call these a 7/10. While there is a decrease in ride quality that you can feel, it’s overall pretty minor. For the most part, the big bumps such as dips in the road, speed bumps, and potholes, the ride quality is about the same – these coilovers can handle that just fine. What you do feel more of is the little things – minor road repairs, cracks in the road, etc. This is both a good thing and a bad thing – you feel the road more, which helps you better adapt to the driving conditions and gives you a better connection with what’s going on outside of the car, but it can also be a bad thing if you just want a super soft ride free of noise or feedback 24/7. Personally, I’m more than happy to take a slight decrease in daily driving comfort for an exponential improvement in track & performance driving, but not everyone will be. My Koni Coilovers from my A4 did excel in street comfort, providing a ride quality that I found superior to OEM for daily commuting activities. And it probably goes without saying, but if you slam your car to the point where your tires rub and you can barely get over curbs, yes, that is something to factor in as well. Personally I just wanted to eliminate wheel gap and improve handling without going for the super low, stanced out look, so I have no issues with rubbing or getting over bumps at about 25″ fender to ground.
I really, really enjoy the STaSIS Ohlins SL paired with my 784/1283 Swift Metric Springs. I experienced unbelievable stability & predictability at the track, and negligible difference in ride quality on the street. I’d highly recommend this setup to anyone that daily drives their A4, S4 or RS4 but wants a car that can really deliver at the track and under other performance conditions.