When you said "bigger" I assumed wider, not diameter of the wheels.
Photography by Tom Suddard
Suspension, power, brakes: There was one more piece of the puzzle for our Mk7 Volkswagen Golf GTI, and it was wheels and tires. We’d shredded the stock tires after all those laps, so it was time to upgrade.
Easy choice, right? Cram the widest Super 200tw tire possible onto the car!
Not so fast: Daily driver, remember?
Much as we’d like to fit one of the latest crop of street tires that are that in name only, they’re not always the most comfortable choice for the street: too noisy, too fragile, and too unpredictable in standing water.
No, instead we decided to move one category less extreme and instead choose a Maximum-Performance Summer category tire. These tires are a bit off the pace of the fastest 200tw tires, but the tradeoff is fantastic street manners, much longer life, and much better performance in wet weather.
Oh, and they’re still durable on track: We don’t want to change tires before every track day, so whatever we picked needed to hold up to the abuse of a track day.
After referring to our own tire testing, we settled on the Continental ExtremeContact Sport 02. This tire is designed to go toe-to-toe with Michelin’s Pilot Sport 4S, and our testing shows nearly identical dry performance and better wet-weather performance from the Continental. Perfect for a car driven daily in Florida rain.
[Tire Test: Continental vs. Michelin on a McLaren MP4-12C]
Our GTI came from the factory with 225/40R18 tires on 18x7.5-inch wheels, and naturally we wanted to go as wide as possible. 034Motorsport cut right to the chase and gave us two options: A 255/40R18 would fit with some minor rubbing, while a 245/40R18 would fit with no issues.
Again, this is a street car, so we resisted the urge to grab the fender roller and ordered the 245mm-wide tires.
Why not take this opportunity to upgrade 19-inch tires? Cost and ride quality: We felt that an even shorter sidewall would provide a worse ride without noticeable benefits at a track day, and the difference in price is enormous: A set of 245/40ZR18 Continentals costs $879.96 from Tire Rack. A set of the same tires in a 245/35ZR19 sells for $1127.96. Seriously, 19-inch wheels would make every set of tires 28% more expensive.
To hold these wider tires, we needed a set of wider wheels. This meant making another big decision: Choose forged wheels, or go with a less expensive construction method like flow-forming? If we lost you, here’s a quick summary: Forged wheels are forged from one piece of solid metal, which results in a wheel with great metallurgy and more strength than a cast wheel.
Flow-formed wheels go by many names (rotary forged, spin forged, etc.), but are made with a less expensive process: First the wheel is cast from molten metal, then some parts (usually some or all of the barrel) are pushed and pulled into the final shape. The result is metal that exhibits certain aspects of a forged wheel, and is stronger than a cast wheel, but it’s tough for any of those forging characteristics to make their way to the wheel’s hub and spokes–most of the benefit is usually focused on the barrel.
What about cast wheels? Thanks to the proliferation of today’s less expensive forged and flow-formed wheels, aftermarket cast alloys have become a less common option these days.
The tradeoff between forged and flow-formed wheels is pretty simple: Forged wheels are generally lighter and more durable, but that comes at a much higher price tag.
We ended up choosing a forged wheel from Titan 7, the T-D6E in Techna Bronze. They make a perfect size for Mk7 GTIs: 18x8.5 inches with a +44 offset. At about $2200/set, these cost more than flow-formed wheels but less than other fully forged options.
Our new Titan 7 T-D6E wheels wrapped in Continental ExtremeContact Sport 02 (left) versus the factory wheels fitted with Hankook Ventus S1 Noble2 tires (right)
How did we make the decision? And why does our daily driver have forged wheels while our race cars sit on flow-formed options?
Our reasoning goes back to this car’s mission: Be a reliable daily driver, even with track use. Our home track, the Florida International Rally & Motorsport Park, requires absolutely murdering the curbing to get fast laps.
And this means occasionally bending a wheel or two. On a race car, that’s not a big deal: Wheels are consumables, and we always have spares in the trailer.
But on our daily? A bent wheel means downtime, a visit to the tire shop, and potentially time out of the office. We figure the forged wheels are good insurance to keep us commuting in comfort.
Plus, they look awesome and weigh nothing–or close to it. Our upgraded wheel and tire combination tips the scales at just under 43 pounds, 2 pounds lighter than the narrower (and bald) stock tires and wheels.
Upgrades complete, we put our GTI back on the ground and stepped back to admire our handiwork. Had we just transformed our daily into the ultimate track day car? Or did these changes mean it was time to put the tow truck on speed dial? We’ll find out in our next installment.
When you said "bigger" I assumed wider, not diameter of the wheels.
This is one of the things I'm really opinionated on:
If it's just a daily / HPDE car; why on earth would you increase your running costs with super sticky tires.
For better or worse I put this down to ego (not a dig mine is plenty large). If you are not timing yourself why one earth would you make the car less nice to drive on a daily basis.
Also note I find less grippy tires more fun.
In reply to Tom1200 :
Some of my friends track their daily drivers.... they all carry a second set of wheels with stickier tires in the trunks of their Civics Si and GTIs. They also pad slap them in the paddock before tech (but only in front!). Is this not normal?
Wider definitely isn't necessarily better. I run RE71RS in 235/40/18 which according to Bridgestones data have the same thread width as the 245 but are 1lb lighter. Seen my fastest times to date on those.
My personal fave is the BF Goodrich G-Force Sport Comp S2. It has a unidirectional tread that helps avoid hydroplaning. I have an NB Miata and hydroplaning is my primary fear. They're no longer available for my car, but unidirectional tread is what I always require. If you can find a size that works for you, get'em!
I do more spirited street driving then track driving these day. Use to use summer set and a winter set but a while ago switch to one set. I have had two set of DSWs in the past but found they were great in the snow and rain but the side walls where weak and gave a very unresponsive steering feel. So this time went with BFGoodRich G-FORCE COMP-2 A/S PLUS, so far much better performance tire then the DWSs. Winter and rain to be determined.
17" wheels fit on this car, correct? Why didn't you downsize from 18" diam to 17"?
Some--the front brakes interfere with a bunch of 17" wheel options, and 17" tires are harder to find, too, so I decided to stick with 18s.
Would be very interesting to see a back to back comparison of a relatively more budget oriented sport compact in the ~$15k range (like a used mk7 gti) with minor upgrades, springs, brake pads, sway bar, alignment, sporty tire, etc. Against a completely stock one of the current fastest options from the factory gr corolla, fl5 type r, mk8 golf R, in the 40-50k price range. Could maybe even find something in the middle of that range to hit the ~25-35k range.
Thinking daily drivable relatively practical with 4+ doors ie. not a miata.
You'll find that right here:
https://grassrootsmotorsports.com/articles/firm-lap-times/
Scroll down a bit and you'll see how this places against the other hot hatches.
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