Tuesday 1 March 2016

On This Day... Better Brakes 100

On this day 30 years ago the 1986 Australian Touring Car Championship kicked off with Round 1: the Better Brakes 100 at Amaroo Park, just outside Sydney.



Amaroo Park isn't there anymore, which is a shame, because it was a great little circuit. Tight, short and hilly, Dick Johnson summed it up with his usual style: “You’re never straight round ‘ere! And when your tyres are off, you’re not even straight going up the straight!" It was hardly the place to bring a V8 muscle car or a laggy turbo monster – but of course the Group A era featured plenty of both. Amaroo had a glorious 80's and a pretty good first half of the 90's too before closing its doors, at last succumbing to the death pact inherent to a lot of motorsport venues: to get bums on seats you have to be close to a major city, but major cities tend to grow and sooner or later they swallow you whole. By the late 90's the land Amaroo Park was sitting on was too valuable to stay in the hands of a business as unprofitable as motor racing, and it would only be a matter of time before the noise complaints came rolling in, and the council would apply noise restrictions that would kill its credibility as a serious venue... so it was sold and subdivided and turned into housing nobody can now afford.

But for about 20 years, Amaroo was a little Mecca all its own. It ran its very own single-track touring car championship call AMSCAR, for example, which was a prestigious title to win – even if it got no media attention, it signalled a driver was a major talent for the future. As it did Jim Richards in 1985, who went undefeated at this track all year, winning nine AMSCAR races, the ATCC round, and the endurance round before Bathurst. It was Robbie Francevic who broke the streak here in 1986, opening his bank account with a win on the way to his first and only Australian Touring Car Championship this same year. The season was due to unfold a lot like Jenson Button/BrawnGP in 2009 – Robbie won a bunch of races early on and gained a huge lead, but had to fight hard to keep it as everyone else got busy developing their cars and started leaving him behind. The reason for that was the nature of the car itself.

Spotlight Car: the Mark Petch Volvo 240T
It really was a case of the Volvo, as in the only one, and not the usual arrangement of a handful of chassis, engines and tyre sets put together on a mix-and-match basis. The Petch team had only one car and two engines, and raced the same car for almost 18 months before they got their hands on a second car – which even then usually wasn't as good, and they often fell back on Old Faithful here. But more on that later.

This is actually a replica built by a fan, but I share it here because it shows the livery the car ran in for the first few rounds of '86. Petch's seals business couldn't provide enough cash to run the car for a second year, so they found a sponsor in Castrol. Later they found an even richer, but much more troublesome sponsor. (Source).

It had originally been built in Belgium by GTM Engineering and raced in the '84 ETCC by Pierre Dieudonne of the Belgian Volvo Dealers outfit, meaning it was built in Eurocentric Left-Hand Drive. When its European season was finished, it was bought by businessman-enthusiast Mark Petch in New Zealand – the Group A rulebook was about to be adopted in Oceania, and a proven car like the Volvo seemed a good bet. His plan was to co-drive the car himself with Dieudonne in the inaugural Wellington 500, January '85, but that idea was shot down when Dieudonne demanded to be paid. Petch dumped him in favour of teammate Michel Delcourt, who'd work for free.

Unfortunately, Delcourt was a huge guy, way bigger than Dieudonne or Petch – it was the same Delcourt who'd later break the seat in Gricey's Commodore at Spa. The mismatch between Delcourt and Petch made sharing the driving impractical, so Petch called in 1967 New Zealand Saloon Car champion Robbie Francevic instead. Petch today often shows up to settle arguments on Kiwi motorsport forum The Roaring Season, and had this to say:
When I met Michel for the first time and saw what a huge man he was, I was jolly
glad I didn’t have to try to drive where he had the seat and steering wheel positioned.
Fortunately it was near-perfect for Robbie, so that was it really.
So that race brought together the three major elements in the equation – Robbie Francevic, Mark Petch, and the Volvo 240T. Having won Wellington, the three of them decided to see how far this relationship could take them and tried their luck across the Tasman in the '85 ATCC. They ended the season with a couple of race wins, but also a lot of retirements and a reputation for wild driving, which was odd when Robbie was as experienced as he was (he was 42 years old at the time). After retiring from the Eurovox Trophy race at Calder Park, Peter Brock was asked whether he'd had a tyre problem or a valve problem, and snarled: "I didn’t have a tyre problem or a valve problem, I had a Volvo driving into my left-hand door!" A moment later he calmed down and admitted, "I don’t know how Robbie drives – I guess we’re finding out. That's motorsport."

In its old life as a GTM Engineering car, Silverstone 1984. (Source)

Part of it might've been that he was still learning how to handle the Volvo itself, and that piece of machinery was changing practically every week. Finding out what parts are fitted to replicas and surviving historical cars is fairly easy; finding out what they were running back in the day is damn near impossible, so this list shouldn't be regarded as authoritative. Nevertheless, as best as I can discover, the engine was a Volvo B21ET, a two-valve, 2,127cc inline-four boosted by a Garrett ART T3/T4 turbocharger. The block was hardened, as were the forged 1986 Evo 2-spec flat-top Mahle pistons. The crank was forged, the exhaust was a special 3" system, and the car used special ported alloy heads made by Grottis in Sweden, famous for building the best heads in Group A.

The intercooler was an all-aluminium alloy job, hand-built by Längerer & Reich in Germany. Fuel injection was via Bosch K-Jetronic CIS with Bosch “gold” injectors, a race-spec injector made especially for Volvo. Ignition was via a Volvo/Bosch E-ZK Ignition system, controlled by a 14-sensor programmable ECU including a “knock sensor,” modified for more map points (Volvo were one of the first companies to use programmable engine management in Group A). A second ECU controlled boost pressure and water injection. The static compression ratio was a low 7:1, but typical race boost was around 1.55 bar, which came on at 3,000rpm and reached peak power – about 260 kW – at 6,500rpm.

The gearbox was a Getrag M51 sport 5-speed dogleg, connected to a single-plate competition clutch and a racing-spec LSD (the diff was free under the rules, but had to fit in the standard housing without any modifications). Huge Lockheed brakes were fitted with ventilated 330mm discs on the front and 280mm at rear. The suspension was adjustable (one of the first cars to use adjustable suspension in Group A), with control arms originally developed in Australia. Multiplying the engine capacity by 1.4, as required by the rules, placed the Volvo in the 2,500cc class, meaning it ran on the mandated 10" tyres, while weight estimates range from the 1,035kg laid down in the rules, to “slightly over” its 1,065kg class limit, to a rather beefy 1,140kg. In the cockpit, all trim had been removed, except for the dash which had to stay where it was. All 240Ts raced with the ‘82-spec flat bonnet, grille and surrounds, because it was a little more aerodynamic. The body shell was production-standard (although some were acid-dipped for lightness), and a thinner windscreen was fitted.

Of course, given all the hard work the Petch team put into getting it to handle properly, you could probably throw half that list away offhand: mechanic Wayne Eckersley later revealed that over the course of season '85 they'd changed just about everything on the car trying to find a workable setup, and by the final round at Oran Park they'd decided the only thing wrong was that the shocks weren't man enough to cope with the stiffness of the springs. As a solution Petch had flown in a new set of shocks just for the race, and in the morning warmup everyone went white when Francevic hit the track with race tyres and a decent fuel load and did a 1:16.1. Pole position for that race had fallen at 1:16.3. The Volvo was a goer... too late for 1985, but locked and loaded for 1986.


You can see the confidence that gave Robbie in the way he drove in the Better Brakes 100. The wild exuberance of last year was gone; this was Robbie putting in a drive both mature and polished. The race was decided by tyre wear, and Robbie was very careful to manage that in the early stages, knowing his turbo engine should've made for a car that wanted to go everywhere sideways. Early contender George Fury, for example, was out on lap 20 with tyre problems, though that wasn't strictly his fault – a wheel bearing had failed and the head buildup was blistering the tyre from the inside.

But Francevic kept it tidy, and It was only in the last few laps he started getting out of shape, the Volvo starting to glide through the turns in some lovely oversteering drifts. But by then it was already in the bag – the V8 runners had shredded their tyres long ago, and Jim Richards in his serpentine BMW 635 had left his charge just a bit too late. The last few laps while Jim hunted him down were exciting, but Robbie held it to the chequered flag with Gentleman Jim still three car lengths behind. “That’s what you call a well-judged race, isn’t it?” said Robbie breezily afterwards. Naturally, Jim congratulated him, but added with a smirk, “That’s exactly what I would’ve done...” So Robbie opened his 1986 bank account with a perfect 28 points (25 for the win plus a bonus 3 for an engine under 3.0 litres – no, the scoring system didn't take account of his turbo), ahead of Richards and Longhurst on 23 apiece, with the top five rounded out by Dick Johnson on 17 and Peter Brock on 15. It would be an awful long way from here to the ATCC trophy, but this was the best start he could've hoped for.

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