Project B6 A4: Phase Four – Wheels, Tires, Brakes, Intake and Exterior Finish
The last installment of our Project B6 A4 was definitely an interesting one, and was meant to put the final touches on our car and call it a day. Previous attention had been concentrated on improving the performance and handling of the car, while later on we looked at lightening up the car, maximizing grip and stopping power and letting the engine breathe better.
As we were modifying the car we had originally thought that a front mount or dual mount intercooler was in our future, but then decided against it for a couple of reasons. First off, the cost of an intercooler is pretty substantial. Second, significant modifications to the front bumper assembly to install the intercooler just wasn’t going to cut it. Northern California can generate heat soak for a few of the summer months, but in the end we scrapped the intercooler idea altogether. So, how did it all pan out? Read ahead and see for yourself.
Our good friends at Neuspeed (Neumann Distributing) have decided to expand their aftermarket array of products to include light weight performance wheels. Upon seeing the initial images of their new wheels, we determined that we had to get a set of these forged wheels for our car. We contacted both Bill and Gary Neumann and talked to them about our options.
Eventually we went with the very lightweight RS10 wheels in 19X8.5″ size with an offset of ET35. Two of the main benefits of these wheels are their very distinctive sporty look and their ability to be easily cleaned. The most important aspect, however, is the low weight nature of the wheels. Amazingly, even in this 19″ size the wheels only weigh a mere 19.5 lbs each.
With Audis continuing to put on the pounds these days, it is always good to find some way to decrease unsprung weight. We opted for the clean look of the silver center wheels since it complimented the Dolphin Gray color of our project car.
You got expensive wheels, right? You don’t want to lose them to Midnight Auto Supply, right? Do yourself a favor and get some nice wheel locks and protect your investment. We obtained a set of these since we didn’t want to come out to our driveway in the morning and find the project car on cinder blocks and the nice Neuspeed wheels and Toyo tires missing.
Mike Kim at Pure Motorsports in SoCal set us up with a nice set of RAD wheel locks. These locks protect while not drastically diminishing the visual appeal of the wheels themselves. The only thing about wheel locks is that you have to make sure you include the wheel lock key in the car at all times. Imagine getting a flat on a busy freeway and trying to remove a wheel only to realize you didn’t have the key!
After considering a number of tires available in the market today we contacted Toyo Tires for an update on their recently released T1R tire. We had had good experience with the T1S tires in prior Audi vehicles and were interested in how the T1R improved upon the T1S.
After an initial limited release, Toyo was eventually able to send us a nice set of four 235/35-19 tires for our project car. The mixture of the wheels and tires drastically improves the looks of the vehicle and actually gets a ton of “thumbs up” gestures from pedestrians.
The performance of this matching of wheels and tires also gets high marks in the handling department because freeway onramps now become the equivalent of E ticket rides at Disneyland. As the initial rubber gets worn off the tires, these tires improve like a nice bottle of Cabernet. They get a “highly recommended” notation from us in the dry, but only satisfactory rating in the wet. You can’t be great at everything.
When we initially looked at what Audi of America decided to use for brakes on the US version of the B6 A4 1.8T, we were actually quite appalled. The OEM front and rear brakes were not even close to acceptable for the typical AudiWorld forum visitor.
The first visit to the track in OEM format produced extreme brake fade during the second lap on Infineon Raceway in Sonoma CA. It was clear that these stock brakes just would not suffice. So, the search began for a realistic alternative for both occasional track use, at one of the many Audi Club Driver Safety Seminars, for daily commuting and for an occasional jaunt in the local canyons.
We considered the latest lower-cost release by Brembo for this application, but decided the 328mm front rotor size just didn’t make the cut for our use. We also considered the larger 355mm Brembo option, but the high cost (due to its manufacture in Italy) made us consider other alternatives. StaSIS Engineering’s Alcon alternatives were also considered (as was the big brake kit offered by ECS Tuning), but in the end the 355mm Stoptech front big brake kit got the nod.
There was just something about those bright red calipers to accent the “modded” status of the car. In NorCal, Stoptech has been providing excellent customer service both on the phone to their end users, to distributors, and even at the track. Due to this client centric mentality Stoptech has gained a very good following for those individuals that want to get a good bang-for-the-buck brake upgrade at a reasonable cost.
We were initially going to go with the 332mm kit, but decided “what the heck” and clicked it up a notch to the larger 355mm kit. You can never have big enough brakes, don’t you think? Cross drilled and slotted rotors were considered, and slotted won out in the end. Cross drilled look nice, but in terms of performance we thought the slotted were more likely to give us better stopping power. Time will tell if we made the right choice on that decision.
Achtuning, a west coast Stoptech distributor, provided the 355mm kit, Motul RBF600 brake fluid and a set of standard Axxis metalmaster brake pads for street use. We then contacted Matt Weiss at Stoptech and got some rear steel-braided brake lines and a nice set of Pagid Orange front brake pads for exclusive track use. As you might have heard from Matt, or read in the Stoptech literature, the pads that come with the brakes, Axxis metalmasters, are NOT designed for track use. They are however very suited to daily driving rigors.
Maximizing performance wisely and cost effectively has always been the goal of the modifications of this project car, and the intake aspect of this car is in line with those goals. When we considered an intake for this car, we could only think of one alternative: Carbonio.
Of course we could have designed and manufactured a custom set-up, but didn’t have the time or energy to do so. We wanted something that not only worked well, but looked nice as too.
We called our buddy Stephen Hooks of Audi Performance and Racing (APR), the exclusive US distributor of Carbonio products in the US, discussed our needs and a few weeks later we had a nice Carbonio intake system on our doorstep calling to us to “install me..install me now!” We not only wanted to install this system but we also wanted to log the data associated with the change.
What you see in the graph is the result of the change, and we think this is very significant. It looks to us like intake temps decreased on average about eight degrees, which translates into a significant power increase and associated better throttle response. Besides the performance, the look of the unit is quite impressive. You can tell the folks at Carbonio put a lot of effort into the design.
We do have a few nitpicks about how the unit fits, and hope Carbonio hasn’t closed the book on refinements to this specific application. What are they you ask? Well, the unit doesn’t quite line up with the firewall, and the intake plenum coming from the grille area could not line up properly to be able to use both OEM screws. Little nits, we know, but nits just the same. We do understand that tolerances will change from car to car, so maybe this issue was more prominent in our particular application and not indicative of others.
Of course after all these modifications we had to see how the final product worked at the track. We took the car to Thunderhill Raceway Park in Willows, CA for the two-day 9th Annual ACNA Driver Safety Seminar. We also rounded up some track wheels (18X8.5″ SSR competition) and R compound track tires (Toyo RA1 – 235/40/18). The result was very impressive. The car has definitely got mojo now – lots of it. It is powerful and handles beautifully. We decided to run 100 octane gas to get the most out of the car and we were definitely impressed. The car brakes well with the Pagid orange brake pads, with no fade whatsoever after repeated 25 minute track sessions.
Some Final Comments
With our AudiWorld project car we set out to show one way of modifying a B6 A4 1.8T sedan. Yes, we understand that we could have used other components, we could have made this into a Stage 3 car and we could have enlisted the help of other tuners and manufacturers of products. We chose one way to do it. We think it turned out quite nice. We made a very nice looking, albeit mediocre performing car, into quite a nice performance sedan. Our goal was to help the reader consider some different alternatives.
We want to thank all the vendors involved in this project car since without them we wouldn’t have nearly as much fun.
OK, onto our next project. Stay tuned.