Spa is quick still. Sebastian Vettel’s fastest lap at the Belgian Grand Prix equated to a 141.457mph average – despite the hideous Full Stop chicane opposite the pit entrance. The Red Bull was a fraction more than nine seconds quicker than the fastest Audi diesel-hybrid from May’s six-hour World Endurance Championship race.

Marcel Fässler, André Lotterer and Benoît Tréluyer lead the Spa 6 Hours

Kimi Raïkkönen’s qualifying best on Saturday – 1min 48.296sec (set in Q2) – was a fraction over ten quicker than the pole-sitting Audi.

There was a time, however, when sports cars were the quicker at Spa.

In 1970, Pedro Rodríguez, ostensibly circulating to bed in pads for the race, lapped in 3min 19.8sec to beat his JW/Gulf team-mate Jo Siffert to pole by 4.1sec. In the Spa 1000km itself, he found another three seconds for an average of 160mph. He didn’t win.

Jo Siffert and Pedro Rodríguez go head to head on the run down to Eau Rouge in 1970

JW/Gulf engineer John Horsman reveals in his excellent book Racing in the Rain that a 5-litre Porsche 917 – if fitted with his ‘swept valley’ deck/tail – was capable of lapping this road circuit almost entirely in top gear. The speeds recorded were: 165mph at Stavelot, then a banked, rising, 150-degree sweeping right-hander, and 203mph on the “short Masta Straight”. (An e-tron stealthily mustered 209.4mph in May.)

Horsman also refers to a spate of sudden tyre deflations and the long night spent in a Liège workshop bead-blasting 40 magnesium rims – only three were scrapped – to roughen them to provide a better grip for Firestone’s bead. A brave breed the early-1970s sports car driver.

That same year’s Formula 1 pole position, recorded by Jackie Stewart in a March 701, was 11.5sec slower than Pedro’s banzai race best. In the GP itself, during a determined chase of Rodríguez, now at the wheel a BRM, Chris Amon, also in a March, found another six-tenths for an average of ‘only’ 152mph.

Chris Amon in his March, 1970

There was an excuse for this discrepancy: a chicane, inserted at the behest of the Grand Prix Drivers’ Assocation, at Malmédy, the source of the Masta Straight. Spa, perhaps even more than the Nürburgring, provided the battleground for Stewart’s safety campaign. His critics called it a crusade, but the Scot’s Keystone Kops rescue – it most definitely wasn’t funny at the time – after his crash in the 1966 Belgian GP had understandably coloured his view on unnecessary risk.

Stewart’s powerful clout in F1, as befitting the best of the bunch, can be measured by his clan’s boycott of the old Spa in 1969 and not-so-fond farewell of 1970. Yet Amon, Andrea de Adamich, Howden Ganley, Mike Hailwood, Graham Hill, Arturo Merzario, Carlos Pace, Henri Pescarolo, Brian Redman and Rolf Stommelen – practising F1 drivers all – contested a 1000km at a chicane-less Spa as late as 1973.

Pescarolo leads Amon, Ickx, Bell, Pace and Schuppan, 1973

They did so in sports cars that were to all intents and purposes heavier 3-litre F1s with better aerodynamics. Pescarolo’s sonorous Matra lapped at 163mph. Ferrari’s Jacky Ickx, the most outspoken critic of Stewart from within the brotherhood, had lapped seven-tenths faster yet to qualify on pole.

Malmédy’s GPDA chicane added 6.3sec to Ickx’s fastest lap (158mph) for Matra the following year. Ironically, the drivers reckoned that maximum velocity prior to the Masta Kink was achieved despite the chicane. It was aerodynamics that, according to Amon, removed the “Unnh!” from this ultra-fast left-right sequence. His March had been a real handful there in 1970. Three years later his Matra had it all in hand.

Amon only had himself to ‘blame’. The New Zealander’s freshly be-winged Ferrari was on pole for the 1968 Belgian GP by 3.7sec. Even blighted Chris thought that his day had finally come: a stone punctured his oil radiator and he retired after eight laps.

Amon and Ickx, chased by Surtees and McLaren, 1968

Speeds at Spa made it the natural hatching/fledging ground for wings once F1 had ‘returned to power’ in 1966. Lotus fitted a bib spoiler to the nose of it 49s in 1967, with a view to reducing understeer. It was so effective that it caused oversteer, hardly a relaxing characteristic at 185mph, and Jim Clark and Graham Hill asked for them to be removed. Clark qualified at 151mph even so, half a second faster than Amon would in 1968.

This period generated a handy comparison between sports cars and F1s at Spa. Mike Parkes’ pole for the 1966 1000km would have placed his Ferrari 330P3 11th on the grid for that year’s Belgian GP. Mike Spence’s Chaparral 2F would have been eighth in 1967. And Frank Gardner’s Ford F3L, though seven-tenths slower than Spence’s mark, would have had him sixth in 1968. They were in turn 9.4, 7.5 and 7.7 seconds slower than the corresponding F1 poles.

The Mike Spence/Phil Hill Chaparral, 1967

Given the Chaparral’s high adjustable rear wing and the DFV-powered F3L’s super-slippery shape, this represents the locus of the burgeoning understanding of downforce and the known benefits of low-drag. Either way, however, the old Spa could not continue beyond 1975.

The new Spa was ready in time for Group C in 1982 and F1 was coaxed back the following season. Alain Prost’s Renault RE40 held 4.7 seconds over Jochen Mass’s Porsche 956 in 1983; it would have been more but for a wet second session. By 1985, the Frenchman’s McLaren MP4/2B had 10.6sec in hand over the pace-setting Lancia LC2. The corresponding annual qualifying time gaps thereafter were: 12.5, 12, 8.5, 15 (a damp track for the Group Cs) and 8.9 – all in F1’s favour.

Mauro Baldi’s Sauber C11 dipped under two minutes in 1990. Three months later Ayrton Senna left his McLaren MP4/5B teetering on the edge of the 1min 40s.

Senna at speed, 1990

Sports cars were/are approximately 10 seconds in arrears. Let’s call it five years. But if racing is for you all about outright speed and noise, ‘Pesca’ aboard his Matra MS670B at Spa in 1973 has never been surpassed. (With apologies to Messrs Ickx and Ferrari.)

PS Vettel has won 12 of the 22 Grands Prix held after the last European round of the past four seasons. This suggests strongly that the Italian GP is make-or-break for Messrs Alonso, Hamilton and Räikkönen.

Monza’s still quick, too. And the RB9 was fastest through the speed gun at Spa.

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