Track Battle: Porsche 911 GT3 RS vs McLaren 750S vs Radical SR3 XXR

Introduction

Some track tests are close. This one was not. We took three cars with three completely different philosophies to a twisty home circuit and ran a proper lap time leaderboard: the reigning Car of the Year and Track Car of the Year, the Porsche 911 GT3 RS; the McLaren 750S; and the new Radical SR3 XXR. At Anglse, a circuit without huge straights but with an awkward mix of heavy braking zones, fast sweeps, and tight, twisty corners, each car had moments where it could shine. The result surprised us, and the way each car felt lap after lap told an even more interesting story than the clock.

How the Three Cars Compare

On paper, this is a fascinating mismatch. The Radical weighs about half as much as either road car and rides on slick tyres, which give it a genuine grip advantage. The two road cars run the most extreme road-legal tyres available, so the grip gap is real but not enormous.

The McLaren brings serious firepower: 750 horsepower against the Porsche’s 515. The Porsche answers with an incredible set of active aerodynamics, including an enormous rear wing that sits higher than the roof and active front wings, delivering a huge amount of downforce. The circuit shape matters too: heavy braking areas punish weight, while fast corners reward grip and downforce, so different cars peak in different places.

A good track day car needs enough power to be exciting, but also lightness and agility so you can brake late and throw it around in ways you simply cannot on the road. Before the runs, our pick was the Porsche, on a fresh set of Michelin Cup 2 R tyres, simply because it is such a capable car everywhere.

Porsche 911 GT3 RS: The Consistent All-Rounder

The 911 GT3 RS is such a special thing. It does not drive like anything else, including other 911s. Once you learn to use the revs, it feels completely at home on track while remaining remarkably approachable. In the high-speed corners the aerodynamics work their magic and the car feels super stable, yet it is equally predictable at low speed. You can lean on it, use the curbs, even be a little brutal with it, and it takes it lap after lap without the lap time dropping off.

It is also deeply adjustable. With more time you could keep finding time, or tailor the car’s behaviour to your preference and any circuit you visit. In our running we left the differential in a neutral position, stiffened the dampers for the warm, grippy track, and let the aero sit in Dynamic mode. And the bandwidth is astonishing: on the cool-down lap into the pits, the radio traffic news came on. You can lap hard all day and still listen to a podcast on the way home. For consistency, tyre and brake longevity, and sheer drivability lap after lap, this was the better car throughout.

McLaren 750S: Power With a Wild Streak

The 750S is brutally quick around a circuit like this. All the straights seem about 30 percent shorter when you are in it, and it changes direction brilliantly. But it rotates so quickly that the rear is always working hard, so when you pick the throttle back up it is easy to light the tyres up. Out of the hairpins in third gear it still spins them, which makes putting the power down a genuine job.

We ran with driver aids off because they inhibit the car too much, including the variable drift control that lets you choose how much slip you get. It turned out to be quicker with everything off. It is a wild animal, but a controllable one: even when grip breaks away, you always know where you are with it, thanks in part to the stiffness and consistency of the carbon monocoque. The trade-off is the tyres. They are very soft and deliver their best over only a narrow window of a few laps before falling off, so finding a quick time means hitting that sweet spot.

Radical SR3 XXR: The Lightweight Track Weapon

The Radical is a different world. With roughly 232 horsepower against 515 and 750 for the road cars, it wins through sheer lightness and slick tyres. There is a corner where you brake in the Porsche, yet in the Radical you are changing up from fourth to fifth. Your brain tells you to brake, but you have miles of space, so getting near its limit takes a leap of faith.

It changes direction in a way no road car ever could, and there is no movement in any tread block, so every steering input translates straight to the front wheels. The road cars feel more immediately familiar but get harder the faster you push. The Radical does the opposite: the harder you drive it, the easier it gets, once you trust it. There is nothing else like it.

The Lap Times and What They Mean

The Radical was quickest by quite some margin, around a 106.4, faster than we expected, which shows that slick tyres, a low centre of gravity, and low weight will always come through in the end. The Porsche and McLaren were separated by mere tenths, and despite our prediction the Porsche was the slower of the two on the clock, though it felt the better car throughout the lap.

On the wider leaderboard, the Radical is the second quickest car ever timed at this circuit, beaten only by another non-road-legal track machine, the Revolution 500 Evo. The McLaren was a couple of tenths slower than the 720S previously timed, which could be conditions on the day, or the extra torque and shorter final drive making it spikier to drive.

Which One Should You Choose?

Our testers split, which tells you everything. One picked the Radical outright, loving how deep you can dig and how everything you put in, you get back. Another chose the Porsche for its staying power, consistency, and the surprising way it mixes hardcore performance with approachability and rich adjustability. If we could build a Frankenstein hybrid, we would take the Radical’s nimbleness, the Porsche’s exploitability, configurability, and engine note, and the McLaren’s addictive straight-line power all day long.

Conclusion

Three cars, three philosophies: the McLaren for raw power and drama, the Radical for pure track focus, and the Porsche 911 GT3 RS for a blend of both that stays usable lap after lap. If you want one car that does everything a track day asks, the GT3 RS remains an extraordinarily complete answer; if you want the outright fastest thing on the day, the Radical’s lightness and slicks are simply unbeatable.