Mk7 GTI: Get better lap times without adding more power

Can your daily driver serve as your track car and vice versa? And can this hypothetical car be a used Volkswagen?

So far, it looks like the answer is “yes,” as we’ve been cruising around in air-conditioned comfort and visiting the race track every chance we get. No truck, no trailer, no tire changes, no drama: Just a 2017 VW GTI and a helmet, and hours and hours of happy track time.

But it seems wrong to rest on our laurels, so let’s turn up the difficulty a few notches and start modifying the car.

Can we make the GTI faster without breaking it (or breaking the piggy bank)? And will additional speed come with downsides on the street? Let’s hit the garage and find out.

First, though, a note on our methodology: Sorry, but we won’t be scientifically testing every single upgrade one part at a time on this project.

Why? Well, honestly, we don’t think that fits the mission here: Nobody repeating this experiment in real life would, for example, install fresh tires without fixing the alignment, and they wouldn’t add camber plates without also changing the front springs while the car is apart.

We’ll be changing a few parts at a time because that’s how the average person modifying their daily driver would do it, and because we have years of experience to lean on when it comes to choosing upgrades and anticipating their effects.

Want a more rigorous, scientific process? Head on over to the LS-swapped 350Z or the LFX-swapped Miata projects to see what upgrading a dedicated track car looks like.

Before we start modifying, let’s lay the ground rules: This is theoretically our only car, remember? So we can’t leave it disassembled on the lift for days at a time.

In fact, we’ll go a step further and say that every single upgrade has to be doable in a single weekend, without specialty tools or significant expertise.

Why use a two-post lift with these constraints? Simple: Because you like to see photos of our projects, and shooting is infinitely easier with the car up in the air. But every upgrade we’ll discuss could easily be handled on a set of jack stands.

Oh, and you’ll notice a recurring name in this update: 034Motorsport, a Volkswagen and Audi tuning firm. Why’d we use so many 034 parts? Simple: They’re fans of GRM, they’ve provided tons of advice and expertise, and they make nice stuff. We’re big fans.

Ground rules set, let’s get to work. And the first item on our wishlist? More camber!

What’s camber? Feel free to watch a more detailed description in our video below, but here are the basics: Negative camber is when the top of the tire leans in towards the middle of the car, while positive camber is the opposite.

Tires work best when their entire tread touches the ground, and when our GTI experiences body roll in corners, its outside tires have positive camber, particularly up front.

This is bad for a few reasons: It reduces grip and causes understeer, and it causes premature tire wear. Adding negative camber should make the car faster, more fun to drive, and less abusive to the front tires: In other words, it’s a win-win-win.

[What is Camber, caster and toe? | Handling basics]

So how do you add negative camber? For a MacPherson-strut car like our GTI, the easiest way is via camber plates, which replace the factory upper strut mount with a new one that moves the top of the strut, and therefore the top of the tire, in toward the middle of the car.

The aftermarket has a bunch of choices for Mk7 GTI camber plates, but we quickly zeroed in on 034Motorsport's Dynamic+ Camster Mounts. At $373, these aren’t adjustable like some other options, and they don’t add as much negative camber as the competition.

So why’d we pick them? Precisely because they’re a milder option: Infinite adjustability and spherical bearings are great for race cars, but we’ve found that some can be an NVH nightmare on street cars.

034 Dynamic+ Camster mounts keep the OEM-style rubber bushing, which should translate to a quiet, comfortable ride like the factory parts. And their fixed adjustment–an additional 1.5 degrees of negative camber and 1 degree of additional caster–should be perfect for this application.

What’s caster? Check out the video above, but TL;DR: It’s a good thing for your track car. 

Installing camber plates on a Mk7 GTI is, well, sort of horrible: You’ll need a set of triple square bits and a strut spreader tool, but those aren’t hard to find. (We found the necessary tools for about $40 on Amazon.)

And it’s not a difficult job, either, as every step is obvious and straightforward. No, the real chore is actually separating the front strut from the knuckle, which took two people and the largest crowbar we owned. Thanks, Volkswagen. We hated every minute, but did eventually get the struts out.

With the front struts out of the car, we pulled the factory top hats off and put new springs in.

Wait, what? Yeah, you read that correctly: It seemed silly to go this deep into the suspension without taking the opportunity for a spring upgrade, so we did. And again, we skipped the aggressive track-oriented options and chose something milder from the 034Motorsport catalog: At $295, their Dynamic+ lowering springs are pitched as an “OEM+” upgrade, but that’s no way to choose a spring.

We had two conflicting goals to balance. First, our desire to keep the car’s spring rate, ride frequency and comfort levels as close to stock as possible. Second, our desire to lower the car, both to reduce weight transfer, increase negative camber and, honestly, to make it look better.

These springs from 034 Motorsport promise 1 inch of lowering, and rates of 210 lbs./in. front and 280 lbs./in. rear. That’s almost exactly 20% stiffer in the front and rear, and will hopefully achieve our goal of lowering the car without putting it on the bump stops around every corner.

The folks at 034 recommended we pair these springs with–wait for it–stock shocks, which goes against our own advice but might just work.

Generally pairing aftermarket springs with stock shocks will mean an under-damped mess, but 034 Motorsport said its own experience showed that stock, 20,000-mile GTI shocks could handle a bit of additional spring rate without issues.

So, we decided to keep the VW shocks, at least for now. Note that we aren’t upgrading suspension bushings, either: Again, this is a street car, and the installation effort and NVH compromises with polyurethane bushings just don’t seem like a great idea.

Anyway, camber plates: We put the new springs on the OEM shocks, bolted 034 Motorsport’s caster/camber plates on top, and reassembled the front suspension.

In the rear, changing springs is far easier: We undid two bolts holding in the lower control arm, popped the stock springs out, and pushed the lowering springs into place. Success! We ended up with 2.25 degrees of negative camber up front, which should be perfect for a dual-purpose car.

Then we drove the car at night and remembered this isn’t an old Miata: The GTI has adaptive headlights, which automatically level themselves as the car is loaded down with people and stuff.

Now that the car was lowered, the ride height sensor on the rear suspension was telling the computer, “The rear is squatting a full inch! Lower the headlights!”

To fix this, we cheated and broke out a tool the average DIYer probably doesn’t have: Our Autel MaxiPRO MP808 scan tool. It can do all sorts of fun programming, including completing VW’s headlight calibration procedure.

Once we’d taught the car its new natural resting state, the headlights started working correctly again. Don’t have a fancy scan tool? There are a few other options, but the easiest is either the smartphone app OBDEleven or a trip to your local shop to have the headlights calibrated.

What’s next? How about some more power and then a trip back to the track.

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