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From YourSITE.com Technical Features As many upgrades you can do to a car, sometimes replacing your suspension can lead to unwanted results such as diminished ride quality, as well as increased noise, harshness and vibration. Worse yet, a side effect could even be a resulting car that handles even worse than it did stock. In turn, an aftermarket suspension can also provide tremendous benefits in terms of reduced body roll, sharper steering and improved braking. However, as with any modifications, impressions of the results can be highly subjective. While one person may feel that a particularly firm suspension isn’t harsh enough, another may think that their teeth might fall out if the car was driven over rough pavement.
After looking at all the finer points of the two systems, we selected the Variant 3 for several reasons. First and foremost, they were fully adjustable while remaining on the car and do not need to be unbolted or removed to adjust dampening. The Variant 2 requires that you unbolt the rear shocks to adjust the rebound dampening. Secondly, the ability to adjust low speed compression dampening was a real benefit, as it offered a real ability to affect ride comfort and handling. Last but not least, the rear shocks on the Variant 3’s are stainless steel vs. painted steel of the Variant 2, which should help our bay area TT to stay away from corrosion. Having decided upon a suspension, we now needed a place to source it. One of the great things about being members of an online forum community is that many places you might not have heard of before have an opportunity to come to the forefront with their services. One such company is Euro Styles East .
Located in Pittsburgh, PA, Euro Styles East specializes in Audi, VW, BMW And Mini tuning. One quick trip to their website convinced us that this was the place to source our KW’s from. After exchanging a couple of emails and phone calls, the V3’s were on their way to California. Since the TT quattro has fully independent rear suspension comprised of a trailing arm and upper and lower control arms, lowering the car results in too much rear camber and toe out. With this in mind, we contacted Mike at Forge Motorsports, in Orlando Florida. This is the North American arm of Forge Motorsports, which is based in the UK. Since the TT has large following in the UK, Forge has manufactured a wide variety of performance parts for the car, including adjustable rear control arms, which we needed for the Project. Look for us to use more Forge Motorsports performance parts on Project TT in upcoming segments. The Forge adjustable rear control arms are based upon the factory design, but include a poly bushing and an adjustable center so that camber and toe can be brought back into factory spec. The adjustable bar replaces the lower control arm. Depending on how much you lower the TT, you might have to use an additional adjustable control arm on top or an adjustable bushing to be able to dial in the toe settings for the car, as factory adjustability is limited in this respect. With the coilovers and adjustable rear control arms in hand, we headed to Ken’s Performance - a local tire and wheel shop that has installed several suspensions on a variety of VWs and Audis for us in the past. We opted to install the Variant 3’s with the factory settings in terms of compression and rebound, which place the fronts and rears at about 50% stiff in both settings. We felt this was a good place to start, and then make changes as things settled in.
After the suspension was installed, we took the car out for a short drive to settle things down and listen for any unwanted noises, then put the car on the alignment rack to do an initial alignment. Knowing that the suspension would settle some more, we were planning on coming back to do the final settings in terms of height and alignment in a couple weeks. After driving the car for a little over a week, we noticed some unwanted vibration in the steering wheel and knew something was wrong. Thinking it might just be an alignment issue we had the car aligned. Like the Volkswagen R32, the TT has adjustable front camber, as the lower control arm is slotted where the ball joint attaches. It also benefits from different front spindle design (wheel bearing housing) from other pedestrian fourth-generation A-chassis cars whereby the lower control arm is situated 1.325” lower than those on other cars like the first generation A3, and recent Golfs and Jettas here in the States. The swaybar also attaches to the strut body, rather than the lower control arm as it does on other MKIV cars, so there are no issues with the swaybar clearing the driveshaft when lowering the car. This allows the TT to be lowered a reasonable amount without resulting in positive static camber changes when the suspension is under load. Not wanting to negatively affect handling, we set the cars ride height at 1” lower in the front and 1.25” lower in the rear, as measured from the fender lip to the centerpoint of the wheel. This results in a level car, rather than the slight rake it comes with from the factory. We set the front camber at 1 degree negative with .05 inches of toe. In the rear we opted for 1.7 degrees of negative camber, and .13 inches of toe. While the front camber is a little aggressive, it was in the midpoint of the recommended settings, and would serve us well on both the street and track. Other settings were within factory spec, with the exception of rear toe, which was just slightly high.
After the alignment, the car did noticeably feel better all around, but we didn’t rid ourselves of the unwanted vibration. One thing we didn’t do, which in retrospect we should have done, was replace the front upper strut mounts and bearings when we did the initial install. Knowing that we needed someone with more knowledge of Audis, we called Tim Tomas of Tomas Sport Tuning in San Pablo California and scheduled an appointment to have him look over the suspension install and replace the strut mounts and bearings. If you haven’t heard of Tomas Sport Tuning, you really need to get out more. Tim’s been wrenching on VW’s and Audi’s for many years and most notably, cars from his shop took 1st place in three categories at this year’s Dubfest in Southern California. Once on the lift, we noticed that one of the struts wasn’t seated properly and that the lower control arm bushings had some pretty serious stress cracks in the rubber. We also noticed that the lower suspension tie bar that was present on the original TT’s was missing. After some investigating, it was determined that Audi eliminated this bar sometime late in the 2001 model year. So Tim installed the new strut mounts and bearings and we were on our way. However, that darn vibration was still with us, although significantly reduced. Figuring it was the worn bushings in the lower control arms, we took the opportunity to order some Powerflex polyurethane front lower control arm bushings and Energy Suspensions polyurethane dogbone engine mount bushings from our friends at TTStuff.com, and a set of OEM rear control arm bushings and the lower tie bar from World Impex and scheduled another visit with Tomas Sport Tuning. TTstuff.com is one of those small independent enthusiast owned and operated companies that we mentioned in the intro article, which surfaced as a result of the need to import some hard to get TT performance items and accessories. Look for more on TTStuff.com on future segments.
We opted for the Powerflex polyurethane front lower control arm bushings to see if we could get back some of the steering sharpness that was lost when the second generation lower control arms were instituted post recall. The second generation or MKII lower control arms as they are often referred to have a very large front bushing, with a large eccentric metal insert. By installing the poly bushing it’s place, we hoped we could replicate the sharper steering inherent in the original design which incorporated a much smaller stiffer bushing. We installed that lower tie bar for that same reason, figuring the stiffer the chassis, the sharper the steering. As for the dogbone engine mount bushings, we figured while we’re down there, we would have those installed as well as some Redline MT-90 in the gearbox, to take our first step and tightening up the shifting on the car. Although it may seem like Project TT has spent more time in the shop than on the road, we can assure you that this isn’t the case. In fact, with all the modifications we’ve done, it’s hard not to want to drive the car. Did we accomplish our objectives? Most certainly. Even without spending much time fine-tuning the dampening settings on the coilovers, we can honestly say, the before and after difference could be described as night and day. The coilovers have all but eliminated excess body roll and the pitch and dive associated with accelerating and braking. In addition, the ride quality over high frequency bumps and freeway expansion joints is improved considerably over stock. We attribute this to the excellent match of spring rates and dampening of the Variant 3’s. Understeer has been greatly reduced and low and behold the steering has been sharpened considerably. Having spent time in an original pre-recall TT, the modifications done to Project TT seem to have brought the newer car right in line with the original. The new lower control arm bushings have also eliminated the vibrations we experienced initially. So, are we done? Not yet. We still want to work with the dampening settings and ride height a little, and also get the car corner balanced prior to taking it to the track. We will be looking at wheel spacers when we install the planned big brake kit upgrade in the future as well as exploring rear sway bar options for the car. However, we want to spend some time dialing in what we have already before making any other changes. We’re quite pleased with the outcome thus far. Related Links: Project TT Main Page www.kwsuspensions.com www.eurostyleseast.com www.tomassporttuning.com www.ttstuff.com www.forgemotorsport.com
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