Porsche 911 GT3 RS and Cayman GT4 RS head to head – which is best?

The GT3 RS is complete. Limb shakingly physical, brain gaspingly demanding, it’s a car you have to limber up for. Shrug your shoulders, flex your fingers, roll your head around your neck, do what you like. Prepare. But you’re still going down.

There’s not much else like it. The McLaren Senna, that’s the car people mention, but I’m not sure even that feels as physical and urgent as you peel into a quick corner as this does. Modern super cars lack edge. I’ve said it myself, that they place speed and capability over involvement. Well done Porsche, for setting me straight. Because the GT3 RS is ballistic, a car with utter, stark staringly furious focus on attack, attack, attack. It’s all it knows. I dread to think what it’s like on the road. Pretty bloody horrid, I suspect.

Haven’t got the spare neurons to think about that right now, because the rear tires are super-heated to 70°C, the carbon ceramic brakes are glowing, the battered air is left trembling and the GT3 RS is delivering a riotous smackdown, clawing demonically into the tarmac, bludgeoning me until I’m punch-drunk. It’s hectic. It’s busy. It’s super stiff and moves around, skips and fidgets, argues and fights. It belittles me. I feel cuckolded. “Get me a proper driver,” it screams, “One who won’t wince and pucker through Follow Through.” Where’s The Stig when you need him?

I’ve been rattling the memory banks but I can’t think of a production road car I’ve driven that comes closer to aping a racing car. To genuinely behaving like one in its manners and methods. Don’t get me started on its snatchy, irritable, grumpy behavior when the brakes and tires were cold. And even now as it’s itchy as it skims over Dunsfold’s innumerable bumps, dips and troughs.

I didn’t time it because that’s Stig business, but it did go through Follow Through at 114mph. I tried the same trick with the GT4 RS and it had a massive, massive moment at 95mph. It let go in a big way where the GT3 RS had shrugged and gone “is that all you’ve got?” while traveling 20mph faster. Mad.

And that one moment encapsulates the difference between these two. Over 400kg of downforce at 124mph from a wing that must have troubled all legislative and regulatory rulebooks, plays whatever flaccid excuse for a spoiler that is that dwells on the GT4 RS’s rump. Until the GT3 RS came along we cooed over it. Now it looks, well… proportionate.

I haven’t talked about engines and performance. The GT3 RS can take everything the 4.0-liter flat six can offer, wherever you choose to offer it. You have direct differential and damping control to maximize that, and as a result it’s not just the GT3 RS’s apex speed, but its traction out the far side that distinguishes it from the GT4 RS.

It’s the same engine as the Cayman, only about 25bhp down (and 35kg down, too). It’s hardly any slower in a straight line and when it comes to noise, the GT4 RS is where it’s at. Those carbon intake snouts behind the doors are black holes, ripping air into their dark depths over the event horizon. It’s a snarl of such savagery and 9,000rpm crescendo, gear after gear that you never want to lift off. It sounds like the GT3 RS feels.

To drive the GT4 RS is notably softer and more rewarding. We never said that at Speed ​​Week when he was in the company of the Ferrari 296 and McLaren Elva. There it felt taut as a tendon, here I can feel a squid. I’ve decided I like squid, especially when it’s this well controlled and the balance as you brake and turn is so good. That’s the difference between these two – the GT4 RS is flattering, its mid-engine balance is more natural and understandable.

As well as bravery, the GT3 RS requires technique and understanding, an ability to use the rear engine to get the most out of the car. That’s always been the case with the 911s, but here such is the delicacy and subtlety of its responses that it’s like you’ve accessed whole new levels. Smooth tracks it must just monster, bumpy ones take guts, commitment, ability and intelligence.

And the brakes! Only two cars we’ve ever tested have stopped faster. Another Porsche, the mighty 918 Spyder, and McLaren’s 720S. This, stopping from 100mph in 74.6 meters and pulling a peak of over 2g, improved everything from a McLaren P1 to a Ferrari SF90.

A word on value. For the experiences and abilities these two offer, they’re bargains. Both are utterly captivating to drive, cars that set new standards for track focus and road engagement. You know which is which. Pay £178,500 for a GT3 RS and you would have to add all the racing bits. Call it £210k. For £113,700, the GT4 RS is one of the great bargains of our time. It doesn’t need the cage and magnesium wheels. I’d drive it over any hypercar. I’d have it over the GT3 RS…