Track tyre test: Road tyres vs Track tyres

"Six seconds is big, that’s a whole other car”. Elliot Barbour, our tame racing driver, is almost picking his jaw up off the gritty Winton garage floor as he is told the difference in lap time between two sets of tyres he’s just tested. This is using the same car, at the same track, on the same day.

Six seconds is stark; that’s the difference between a Mercedes-AMG C63 S and a 991-series Porsche 911 GT3 around one lap here, Winton’s full 3.0km circuit, as we precisely demonstrated at our 2016 Performance Car of the Year.

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The Porsche might be in another league for performance and speed to the AMG but, crucially, it charges an extra $155K for the capability. So imagine making the same sort of quantum leap with a few hundred dollars, by way of spending extra on the oft-forgotten black and round things beaded on to your probably large and expensive wheels.

Yes, a conversation about tyres could put an insomniac to sleep, but when this topic comes up, you can tell the real thinkers by those who listen alertly. And so listen up, because the results are in of an experiment we’ve been wanting to conduct for some time.

We’ve grabbed a Toyota 86 GTS with the optional Brembo brakes, packed three very different sets of tyres and headed north to Winton. Pattern number one, from El-Cheapo Inc – we won’t name and shame the actual brand – but from a nation that can make things far cheaper than we can. We actually walked into a tyre shop and said what’s the cheapest and nastiest stuff you have in 215/45 R17.

Against the clock around Winton, we will pit this tyre, the kind your mother would warn you against buying, against a ‘regular’ ultra-high performance road tyre. And for laughs, we will also time a more track-focused pattern. At the end, we will compare times, Barbour’s impressions, and draw some sort of conclusion.

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For the non-lethal rubber, Bridgestone has kindly supplied two sets from its Adrenaline range. First up, the RE003. They’re what it calls its “sports performance” tyres. And while they’re not standard on any road car, their availability in diameters 15- to 20-inches suggests they’ll fit most rides. Price? They’re about double our bargain-spec tyre, depending on where you shop.

Last, but certainly not least, are the exotic set. The Bridgestone RE-71R is a road friendly ‘motorsport’ tyre and represent the Michelin Pilot Sport Cup 2s of the world. With a tread wear rating of 200, compared to the RE003’s 220, they’re certainly streetable. But expect to shell out a bit more than the RE003s for the privilege to try them.

To keep things scientific we’ve asked Toyota for the aforementioned 86 GTS. Its rear-drive platform works its contact patches evenly and a bulletproof atmo 2.0-litre boxer should resist heat soak better than a turbo engine. We’ve also ticked the box on the $2200 optional Performance Pack, with uprated 326mm/312mm discs and fixed Brembo calipers.

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You’ve already met our driver. Barbour has raced everything from Holden HQs to McLaren 650S GT3s since he started professionally competing in cars at 17. Before that he raced karts, but quite literally outgrew the sport. Paired with a Driftbox, he’ll be setting lap times and offer judgement on the less quantifiable things like feel and braking performance.

At a glance, it looks like the El Cheapo’s tread engineers dug the blueprints for the RE003s out of a recycling bin behind Bridgestone’s head office. They have similar lateral sipes on their inside shoulder, then three vertical water channels that sit next to larger blocks on the outside tyre shoulder.

However, something about them doesn’t look exacting or scientific, and Barbour confirms this much once he comes into the pits. “As soon as I left the gate, I put my foot down and it started wheel spinning,” he says, “And I go into turn three there’s just constant understeer, just tyre squeal the whole way around.”

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The lap reflects this, as his best time of 1:47.1sec is slower than any 86/BRZ we’ve punted around here. Pressures are up, too, around 42psi, or 7psi higher than cold, suggesting the tread blocks are squirming.

“There is a delay before they actually bite,” he says. “And as soon as you touch the brake, bang, ABS. I was braking up to 30 or 40 metres earlier in other areas, just to get to an apex. You’re going a lot slower at the apex, too, because you’re carrying brake all the way in.”

The RE003s look way more serious, with big blocks on the outside shoulder and centre ribs. It’s not just a tough tread pattern, either. After their laps pressures lower to a maximum 40psi, or 2psi lower than the El Cheapos, because their tread blocks are stiffer. They also slash 2.4 seconds from the lap time with more grip, at least at the rear, allowing Barbour to keep the throttle pinned on exit at turn one and six.

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However, they’re not perfect. “You can just jump on the throttle at the apex, traction is really good,” he says, “but the biggest thing is allowing it to flow through the middle of the corner.” They’re still rolling over the sidewall, especially at turns three and four. “If we were to put pressures up to something like 40 cold, that would hold the sidewall a bit.”

With them done, we fetch the next set, and the RE-71Rs are instantly recognisable on their aggressive tread design. Only two vertical water channels straddle its solid centre rib, suggesting this tyre is clearly bent on doing one thing: going fast, at least in dry conditions anyway.

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Barbour finds this out first hand. “You can embarrass some other cars on track” he grins. The traces show he’s carrying less brake into turn one than he did on the RE003, committing earlier with speed, but also finding confidence with their compliance to use the kerbs. Barbour reports you can place the car a lot easier. “And you can also adjust it through the corner, you know the directional change is there. Whereas on [the RE003] what you got at the start is what you get to the end of the corner.”

All these improvements piece together a 1:41.8sec lap. The 71Rs produce staggering cornering speeds that shadow the other two. At turn five, Barbour is almost 5km/h faster than the RE003 and 10km/h faster than the El Cheapos. It has to relent some strength, though, “half way through the sweeper around the trees it really rolls the tyre there and it felt very similar to the other ones.”

But the car’s natural grip balance effects how each set feels, too. “The one thing with these tyres, that soft set, is with good grip they induce a lot of understeer.” He then gestures at the El Cheapos, “it will actually turn better in some of the slower corners because it’s got less grip in the rear and will start bringing the rear around a little bit, which I couldn’t make it do on the other tyres.”

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He’s right. Through corners seven, eight and nine the El Cheapos start reeling in the RE003s, beating them through corner seven and 10. Ideally, for a more playful setup, he even suggests putting the El Cheapos on the 86’s rear and the RE003s on the front.

But there are less obvious downsides to our revoltingly cheap contender. “You would smoke through a set of brakes in a day on those,” he warns, as you’re constantly in the ABS.

Sure, you could step up to the RE003s, but for such a small improvement, it really only leaves the RE-71Rs. Barbour agrees. “The most fun I had was on that set because you could really hustle.” These take-home lessons might not be surprising, but they’re worth remembering.

Cheap tyres are fun to burn on the throttle, but spending more on good stuff pays off in more ways than one. You’ll save your brakes and, who knows, might unlock speed that makes it feel like you’re driving a whole other car.

The Results

So, what advantage was gained by running first, rather than last? According to Barbour, not much. Although the track was slippery, by the day’s end he declared conditions consistent. He admits there might have been a second’s difference between the day’s start and end, but most of it would be down to heat soak in the engine. Not enough to change the finishing order.

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