TG joins team Pirelli at the Silverstone Blancpain GT3

The first corner of a Blancpain GT3 race is a pretty awesome spectacle. 55 GT3 racers – most of the current super sports car crop, in other words – wingshod and stickered up, charging for an apex, jostling one another for track real estate. Ferrari 488, Lamborghini Huracan, McLaren 650S, Nissan GT-R, BMW M6, Mercedes-AMG GT, Audi R8, Bentley Continental GT, Aston Martin Vantage, Porsche 911… all those different engine configurations and aerodynamic profiles playing chicken, inches apart…wow.

Photography: Lee Brimble

Course, I’m guessing. I didn’t see 55 GT3 cars scream into Copse at the Silverstone round of the Blancpain GT3. I was tucked away in a corner of the paddock earning my keep with Pirelli. The Italian tyre maker supplies every team of the Blancpain GT3 series with tyres, much as they do in Formula One, and this weekend, they’d agreed to let TG lend a hand with their operation. They have fifty personnel on site at Silverstone. Surely it can only make life easier to make that fifty-one…

It’s a chilly Saturday morning at Silverstone – in complete contravention of the optimistic forecast, but that swiftly ceases to be a problem. I’m led briskly to a quiet corner of the paddock housing four towering tractor-trailer lorries, all in black, with Pirelli logos daubed on the side. On closer inspection, the lorry cabs are all covered in carbon fibre effect wrap. Only the Italians. Anyway, enough fawning over the details: a race weekend’s worth of rubber isn’t going to unload itself. 

While I was sound asleep yesterday, up to 2,500 tyres were being driven from continental Europe to deepest Northamptonshire for their date with Silverstone’s Arena GP circuit. And that’s just for the Blancpain GT3 series. The support race for the series is the Lamborghini Super Trofeo championship, which is a bit like having Foo Fighters play a warm-up set for AC/DC – it’s hardly a poor relation. And it requires a further 1500 black circles of sticky black rubber for the Lambos.

So, altogether that’s seven HGVs full of GT3 rubber, and another three trucks for the Huracan tyres. Each tyre and rim weigh around 20kg, believe it or not, and there’s no automatic unloading system. Tyres are stacked seven high, four deep and approximately fifteen long in the trailer. It smells like one of Vegas’ more unmentionable conventions.

It’s one at a time, by hand, and all of a sudden I’m not at all worried by the chill in the air. Wish I’d done some stretches this morning.

Stacked four high, a set of tyres (worth €1700 a pop) is wheeled into its own little census. Each sidewall has its own individual bar code. Scanning this with an overgrown Blackberry-cum-supermarket checkout bipper reveals which team, which car and which corner of the car this particular tyre is destined for. It means no team can – accidentally or otherwise – use more than their allowed allocation of tyres. Each team is allowed four sets of slick tyres for the race meeting, plus an unlimited supply of sets if the weather turns nasty. Compound tactics? Not here: it’s all Pirelli rubber, just like in F1, and either slicks, or wets. All the performance of the car comes from the pit crew’s set-up and driver talent. But first, they’ve got to come and ask for them...

Each race team will journey to the Pirelli fitting area and place an order for a set of tyres. Each tyre will have the car’s number, the tyre set number, and which corner of the car the tyre is intended for hand-written on the sidewall in Tippex. I scrawl this several times before it becomes legible. The Italian mechanics, dressed all in black and Pirelli-branded aprons, frown and prepare themselves for a long day. 

Before the teams ever get near their tyres, each one has gone through a miniature production line between leaving the carbon-wrapped lorry and greeting its new owner. It’s my job today to assist at every stage of the production line. Having huffed, puffed and just about kept my back in one piece unloading a few sets from the trucks, and graffitied the vital numerals on the sidewall, it’s time to settle the tyres onto their rims. A McLaren wears different centrelock alloys from say, a BMW M6, so attention needs to be carefully paid here. Oh good. 

I’d heard the de-rimming machine going about its business earlier in the day and not been looking forward to it. It’s a pneumatic torture instrument commanded by a variety of buttons and levers that must be pressed for exactly the right amount of time in exactly the right order to get an old tyre off a rim, then in the reverse order to get a fresh tyre fitted snugly back onto a wheel.

Luckily, my teacher speaks absolutely no English whatsoever, and when he kindly does a demo run with an old rim, it’s all over so quickly it’s like trying to learn how to play Smells Like Teen Spirit in ten minutes by watching a Nirvana gig in 140p on YouTube. I make the international sign for ‘one more time, please?”, rotating my index fingers like a crocked footballer begging for substitution. Another tyre finds a new home inside 20 seconds. This time I reckon I’ve cracked the first half of the process, and I’ll probably be able to improve the rest. 

Er, no. I manage to avoid amputating local fingers but my first attempt leaves the used tyre looking distinctly dented, and when I try to reverse the process to retrieve it, I’ve forgotten which button or lever unclamps the damn thing. More gesturing. More feverish Italian. An audience of the Pirelli tyre crew has gathered to enjoy my abject failure at tyre swapping. I try to visualise the big scary machine like a bicycle puncture repair kit and remember how to swap mountain bike tyres, but it’s no good. I can’t speak the mechanics’ language but reckon I know what “this guy couldn’t change a lightbulb” sounds like in Italian.

These guys are pros and the speed and efficiency with which they complete their complicated tasks is mesmerising. They’ve got to be on the ball: wet tyres have their inside rim coated in a lubricant paste which helps the tyre over the rim then acts as a watertight sealant. Slick tyres have an adhesive pasted onto the rim to literally glue the tyre to the wheel and prevent slippage either under brakes or from the racing engines’ torque. You don’t want to be forgetting that.

Mercifully, after humiliating myself with the tyre press, I get shuffled along rapidly to the air hose. Surely, I can put air in a tyre. I’ve done this to bikes and cars before. And it’s less critical here, sort of. Tyre pressures are always set by the Pirelli team to a basic level at the same time of morning, so ambient temperature and air density is consistent. 

The tyres are set at 5-6 bar, but Pirelli always leaves the valve caps unscrewed. Why? This shows the racing pit crews the pressures have not been finalised, and will need fine-tuning by the teams themselves to suit their car, driver and strategy. It’s easy. Fix hose to valve, twist compressor lever, watch the needle rise then disconnect hose. Let the blood run from your eardrums as the CRACK from the valve ricochets through the air, and repeat. 

The final process is balancing – a mix of high tech and the old school. Spinning the tyre on a mechanical axle at around 30rpm detects an imbalance in the tyre. Lights on the machine’s display show where the tyre is unloaded, and sticky pads of lead weight are stuck to the wheel rim then covered in duct tape to rebalance the wheel. I can do this almost unassisted. At last, found my level. Only, I’m a bit off the pace. Pirelli will balance 1400 tyres over the weekend, using a combined 56kg of lead weighting. 

While that’s the end of Pirelli’s well-oiled and professional preparation, the tyres still have more trials to go through before they’re bolted to a third of a million pounds’-worth of racecar.

Once trolleyed over to the pits, teams lightly bake tyres in sealed heater units behind their pit box. Hot air is funneled into the middle of the wheel rim, heating the tyre from the inside out. This is because air pressure inside the tyre, rather than its actual surface temperature, is more important to maintain performance from the rubber itself.  Tyre seats are heated at between 70-80 degrees Centigrade for approximately one hour. If you’re an exhausted journalist who fancies leaning against something in the pits for a breather, take my work for it – don’t shimmy up to one of these tyre cookers.

The tyres will live here until their moment of glory when a GT3 car hoves into the pits for fresh rubber, at which point heavily fireproofed mechanics hurry them into the pit box. A tyre change takes far longer than an F1 pit stop because instead of having three tyre men per wheel (one with new tyre, one to catch old tyre, one on the air gun), only two pit crew are allowed to service the car at once, working around each tyre in turn.

Once fitted to the car, it takes a driver 1-2 laps of a circuit like Silverstone to bring the tyre into its optimum operating window, with a surface temperature of some 90 degrees Celcius. Once the tyre is at perfect temperature and pressure, the tyre gives around six laps of optimal performance during which the driver can really push. After this period, the tyre will lose performance via overheating if the car is driven hard, but the performance drop-off of a ‘gone-off’ GT3 tyre is far less severe than the ‘grip cliff’ deliberately engineered into Formula One tyres.

It’s a massive operation that I’ve been, well, hindering today. And this is just for one race series, at one meeting, on one day. The fifty or so crew that Pirelli entrusts this operation to will be off to Spa, Monza, Paul Ricard, the Nürburgring and more over the course of a season. They’ll have to be on the ball for sprint races and 24-hour marathons. But it’ll be easier next time without the English chap vandalising one of their tyres. Just another 2,499 to go.