Mk V GTI
The GTI is lovingly referred to as "Red Racer." Aside from great suspension, brakes and increased power, it's truly defined by how it delivers that power to the ground. In between the engine and the road is a DSG transmission equipped with a VW Motorsports U.K. limited-slip differential. If you've never driven a car with a true mechanical limited-slip, you're missing out. Being able to put down power with both wheels at the same time may seem a necessity, but only cars with the highest sporting intentions come so-equipped from the factory. An LSD changes the dynamics of the car in ways suspension tuning alone can't touch. Most manufacturers feel that electronic limited-slips are enough, but these are basically nothing more than glorified traction-control systems.
The added motive force won't make a complete car, however. The standard suspension on the GTI is good, but when it came to deciding between mainstream "sporty" and racetrack precision, VW decided mass-market appeal was best. Usually we tend to agree with this for a corporate strategy, but we know enthusiasts like us want more. A set of threaded body coilovers that are both compression and rebound damping adjustable were installed on Racer along with adjustable camber plates. This set-up allows different geometry and damping settings to be tested, but also equates to a car that lives up to its reputation in handling. All the suspension bushings are either solid spherical pieces or polyurethane. The really interesting thing is that VW techs were able to shim the lower subframe forward slightly to gain a little bit of needed caster. This is also something that should be possible for any weekend mechanic with a Mk V.
The brakes were taken straight off an R32. They're maybe not as sexy as aftermarket big brake kits, but certainly as effective. We worked them all day on the track and couldn't get them to give up. They even used factory pads, but we may have opted for aftermarket pads if for no other reason than to cut down on brake dust. The Charleston wheels are O.E. VW as well, available from your local parts department. These were painted black to add a purposeful look.
The engine was augmented with new software and a cat-back exhaust. APR components were used as off-the-shelf alternatives to in-house fabrication, maybe VW just wants to see how this stuff holds up. We'd estimate the car is running just north of 250 hp while maintaining factory driveability and reliability. It pulls hard and will still spin both front tires in first, but second gear is all bite, even out of tight corners.
The combination of all the parts makes for a pretty amazing drive. The car's character really isn't that much different from a regular GTI, but more serious about its actions. The ride is definitely stiffer and not as comfortable, but nothing out of the ordinary for most enthusiasts. This loss of comfort is traded for touring car-like cornering. The better part of the stock body roll is gone and on turn-in the car settles onto the tires nicely with slight weight transfer to the outside wheels without the lifting the insides as on a stock car. Even with the stiff suspension, balancing the car on throttle is still very possible. Lifting results in a nice tuck-in and if combined with a little extra steering flick you can get the car to rotate. Coming out of turns, the LSD really pulls the car on line and keeps it there. On rougher surfaces the car tends to bounce a little, especially when loaded up, but it never upsets the balance.
During braking, dive is reduced, but the fronts are still doing the majority of the work. Initial bite is good and modulation feels great. For even the stickiest street tires the R32 brakes have more than enough stopping power and allow the driver to go deep in fast while easing off while turning in.