Thursday, 9.23am: MIRA Proving Ground, nuneaton, west midlands - Thunderbolts are the least you’d expect. A scorched sky, some localised banshee wailing, perhaps – a pathetic fallacy worthy of an ancient Greek myth.
But the weather is anticlimactically calm and clear now as the very low, very loud and very angry-looking McLaren 675LT rolls to a stop in the car park at the MIRA Proving Ground.
Waiting in the same line of marked bays is the car I’ve driven here: one of only a handful of 2015’s other new model introductions with the potential to deny the McLaren the status that Woking would claim for it.
A nemesis? Maybe not – but a rival, a kindred immortal. Something equally special, too, if not more so. Because if this McLaren isn’t the most exciting driver’s car of the year, the new Porsche 911 GT3 RS may very well be.
Both of these cars were outstanding athletes before their latest performance makeovers. Both, as I’m banking you’ll already have read, have since been endowed with the kind of performance and handling superpowers that are normally reserved for cars with racing liveries. And right now, both are here at the start of a very special 400-mile, 36-hour UK road trip.
This won’t be the average comparison test. Extraordinary cars call for an equally extraordinary opportunity to reveal themselves – and that’s what these two are getting. And yet it’s already too late for a typical head-to-head verdict on the 675LT and GT3 RS. They’re sold out. So, much as we like to imagine there’s a throng of wealthy individuals waiting with bated breath for Autocar’s endorsement before ordering a new car, we can leave the final arguing and justifying aside.
Instead, we will simply find out what life on road and track is like in the company of not one but two of the most hardcore, most wanted sporting machines that this year, or any year, has to offer.
Thursday, 10.49am: MIRA’s mile straights
Our reason for starting at our favourite Midlands proving ground is simple: the Porsche will feature in a full Autocar road test in the weeks to come, and MIRA is where our road test performance benchmarking magic happens. So a morning of flat-out testing lies ahead, followed by an afternoon of photography.
Then it’ll be an early evening blast north-east, onto little-visited moorland roads once used by this magazine’s road testers to become acquainted with one of the McLaren’s legendary forebears.
Standing-start and in-gear acceleration first. I watch the GT3 RS put in a few runs with colleague Matt Prior at the wheel before hopping in myself.
Perhaps the aforementioned banshees have turned up after all. The howl that Porsche’s flat six makes is sabre-sharp and supremely characterful. Porsche’s launch control system makes it sound all the more frenzied, governing it at high revs until the car’s gigantic 325-section rear tyres can transmit 493bhp all on their own.
From inside, the car certainly feels fast – even on a wide, empty, mile-long stretch of perfectly flat asphalt – but, like the GT3, only supercar-fast once it’s revving beyond 5000rpm.
The higher reaches of the Porsche’s rev range feel so special, though, suffused with incredible pedal response and with a visceral power delivery still building until beyond 8000rpm, that you want to stay among them whenever you can. The whipcrack changes of the excellent seven-speed PDK dual-clutch automatic gearbox make it possible to do just that.
Although it’s close on swept volume, the 675LT’s engine might as well be from a different planet. This is a compression ratio of 8.7:1 versus the Porsche’s 12.9:1, twin turbocharging versus Stuttgart’s atmospheric aspiration and 175bhp per litre compared with the GT3 RS’s 123bhp per litre.