Dust thy Neighbor" was part of Volkswagen's print ad campaign for the GTI 16V. The text read something like "...and if you can't beat him in a straight line, there will be ample opportunity in the corners with the GTI's 4-wheel independent sports suspension, front and rear stabilizer bars, four-wheel disc brakes...and so on."
For this writer, a large part of the GTI's appeal was exactly that--being able to defeat more powerful cars via more intelligent underpinnings. In this part of Project GTI, I will address three of the most important parts of the aforementioned equation--wheels, tires and brakes.
Project GTI was born with power-assisted, four-wheel disc brakes linked to diagonal dual circuits. The vented front discs measure 9.4 in. as do the solid rear discs, and there's a self-adjusting parking brake. VW had several styles of 6x14-in. alloy wheels shod with a 205/55-14 tire. Considering its curb weight just over 2,200 lb and 123 bhp, this was a fine match for the GTI, even today. Like everything else on Project GTI, the brakes had suffered from years of neglect, a great way to kill any brake system. There was more water than brake fluid coursing through the crusty lines, and the rubber components had all the stability of used condoms. The original plan was to rebuild the factory's Girling calipers, augment them with braided stainless-steel lines and replace the discs with slotted units from Ate or Brembo. An aggressive brake pad from Hawke, Pagid, Ferodo or EBC would fill the calipers.
Like so many others before it, that plan went out the window. During a photo shoot at Irwindale Speedway, I spied a half-dozen race cars, vehicles used by students in a NASCAR class, outfitted with Wilwood brake systems. These binders must be good, I thought, if they are required to withstand the rigors (and uphold the safety aspect) of a class environment. What's more, in the "closet-o-parts" sat a box from those mad Canadians at RPI, filled with its Wilwood Race Brake kit. What the hell...I'd give it a shot.
The Wilwood kit offers several advantages over the stock setup, the least of which is more swept braking surface area. In this particular application, the rotor increases from 9.4 in. to a whopping 11.0 in. via cross-drilled Brembo discs. According to brake guru Barry Borin at Race Technologies, the Brembo discs are wrought from a higher quality iron than most other rotors and provide superior balance. The rotors also feature an excellent interior vein structure for better cooling.
Another advantage is the design of the Wilwood caliper itself. Carved from billet aluminum, it utilizes four stainless-steel pistons (less prone to corrosion) versus the one chromoly piston in the factory setup, and thus spreads the clamping forces more evenly (in theory). The pads are held in place with one cotter pin, which makes replacing them very easy--a great benefit during race or autocross situations. The calipers' aluminum composition sheds heats much faster than the factory ones, which is a very good thing in braking. In the physics of stopping a car, the brakes transform kinetic energy into frictional heat generated by the pads pressing against the rotors. Quickly dissipating this heat increases the brake system's efficiency and avoids brake fade or, worse, brake failure. The Wilwood caliper is also lighter than the Girling caliper I replaced (5.1 lb vs 8.6 lb), thus saving a bit of unsprung weight.
It should be noted that Wilwood is a serious player in NASCAR--many of those 750-bhp monsters rely on Wilwood binder systems. As described in RPI's catalog, the Wilwood brakes are true race brakes--race brakes are typically noisier than street brakes. They also lack the rigidity of a factory caliper and may require more maintenance. Time will tell if it's a worthwhile compromise.
RPI's Wilwood Race Brake kit includes two 11.0-in. cross-drilled Brembo/PBR rotors, two Wilwood Dynalite II four-piston billet aluminum calipers, two Goodridge stainless-steel brake lines, Hawke HP+ pads, CNC-machined and anodized brackets and grade-8 hardware/fasteners. The Wilwood kit is a simple bolt-on program for most VWs. Each kit is pre-assembled, reducing installation to simply bolting the calipers to the carriers, turning the set screw and installing the stainless-steel Goodridge lines.
While installing these big brakes, it's a good idea to pay attention to the rear binders, too. New discs and inner/outer bearings are recommended, as are the stainless-steel Goodridge lines to help balance the entire system. RPI sells all that stuff, including quality brake fluid.
On 1985-92 Golf and Jetta platforms (with a few late-model exceptions), the procedure is more complicated. It requires different hubs, hub carriers and ball joints from later model VW cars with 10.1-in. brakes. New hub carriers are very expensive, but because they are fairly stout pieces, I opted to purchase a set from FAST (Foreign Auto Salvage Technicians) in Duarte, Calif. FAST is run by the Secor brothers, hardcore VW guys who oversee an extensive collection of watercooled Volkswagen parts. I saved some $200 at FAST and intend to visit their expansive facility on a regular basis. (It would be greatly appreciated if everyone just avoided FAST, thus leaving all the cool, hard-to-find GTI stuff to me.)
Morgan Secor had several hub carriers to choose from, all lined up nice and neat--I was out of there in a matter of minutes. You will most likely need new bearings for the hub carriers, so keep that in mind.
Although the Wilwoods are supposed to work with the stock master cylinder, Project GTI wanted a new one--after the first few stops the pedal went to the floor. I got a new 22mm unit from RPI and things feel much better.
The actual, greasy-knuckle installation procedure is available at our website (www.europeancarweb.com), so now let us backtrack a bit. Following a lengthy search, the ATS Type I wheels I lusted for found their way onto Project GTI, and life was good. I spent hours admiring the "correctness" of them, the "periodness." I was not alone. Twice I was stopped by complete strangers and offered substantial sums of cash money for these 7x15-in. light alloy wheels. Beautiful as they were, however, it was not to be. Although the Wilwoods will clear most 15-in. wheels (using the proper spacers), the ATS Type I is not like most wheels. There was no way the brakes would clear the Type Is. My first instinct was to revert to plan A--rebuild the factory calipers and use them instead of the Wilwoods. I took a long, hard look at these big brakes--were they worth keeping? Were they worth sacrificing my beloved ATS rims?
Given their performance, price and trick appearance, the answer was yes. I would find a new set of wheels to clearance the Wilwood calipers. Despite Peter Wu's love affair with the Volk Racing wheels, I think that particular design is too modern for a classic like his 16V Scirocco (he should have gone with the multi-spoke Volk wheel). I finally found a replacement with Enkei's RCT-1, a strong, high-quality pressure-cast alloy that weighs 16.75-lb (for the 7x16s of Project GTI) and features the 4x100 bolt pattern for the Mark II VWs. The RCT-1 is available in 15-, 16- or 17-in. diameters in white or silver finishes. Enkei is a sizeable Japanese wheel manufacturer that uses state-of-the-art manufacturing techniques and is well respected among the racing community. Rhys Millen's Mitshubishi Evo rally car wears Enkei wheels, as does Adam Saruwatari's 8-sec. Mazda. Although the RCT-1s will bolt up to most VWs with no problem, the tender springs on the rear H&R coilovers of Project GTI rubbed the tire. I used a set of 8mm H&R TRAK+ spacers to clear the spring, while H&R's longer bolts provided the necessary length to fasten the wheel to the hub. The TUeV-approved H&R spacers are hubcentric and cast from a lightweight aluminum-magnesium alloy. I will need to roll the fender lips (or perhaps remove them altogether), but the extra wheel track width is worth it.
Toyo provided the rubber with its Proxes FZ4 tires. The FZ4s are like a cross-trainer shoe, capable of good performance in the dry, wet, mud or snow. They feature an aggressive tread pattern with a 300 treadwear rating, A-traction and A-temperature ratings, which means they will probably last a long time. Although my first choice in Toyo's lineup would have been the awesome T1-S, the FZ4 will provide a good, solid base while Project GTI continues to evolve, and that may take a while. There are a few size options for the Mark II cars shod with 16-in. wheels--I opted for a 205/45ZR-16.
So, how's it all work? Unfortunately, we can't answer that question fairly yet, as we still have some bugs to work out of the system. Tests with the radar gun from 60-0 mph indicated a distance of 137 ft, while old road tests indicate the number should be closer to 120 ft. The front/rear balance is not what it should be, and pedal effort is extremely high. Engineering Editor Dan Barnes suggested some changes to the brake linings' friction material, and a return to a 20mm master cylinder. RPI is sending the required parts. I'll let you know as soon as I get a chance to try them out and do some proper testing. Meanwhile, the H&R coilovers provide a ride that is so good it makes Project GTI feel like a whole new animal. Things are moving forward. Stay tuned.
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