Porsche 911 GT3 versus 911 GTS and Cayman GTS - comparison

This is ostensibly a Carrera S with the optional ‘power kit’ engine upgrade, the same wide body and axle tracks as the Carrera 4 and GT3, and a PASM adaptive suspension system with 10mm of ride height taken out and some firmer settings put back in. It also gets all of the mechanical must-haves of the 991 options list (sports exhaust, dynamic engine mounts, torque vectoring and a limited-slip differential) fitted as standard. 

The specification of the other two Porsches is familiar enough not to need repeating. Neither the 911 GT3 nor Cayman GTS has been through a full Autocar road test – and for sports cars of such incredible stature as these two, that’s regrettable.

Timing was the problem with the GT3. By the time the car’s well-documented engine modification programme had been completed last year and Porsche GB could lend us a right-hand-drive test car, the automotive agenda had moved on.

With the Cayman, we’ve no such excuse. We dared to assume that this was just another series-production, lower-order Porsche. Until we drove it – when it became clear that it wasn’t ‘just’ anything.

Naturally, you’re lured first to the extravagantly meshed and bespoilered, ground-hugging GT3, loitering in a Carmarthenshire car park with all the simmering visual menace of a track prototype. 

From its gaping front air ducts, past its enormous carbon-ceramic brakes to that huge rear wing, the GT3 has true hardcore performance character. It shows up the GTS as a tribute act so pale by comparison that you’d think the gap between their respective prices was more like £90k than £9k.

Not that you can order your own £100,540 GT3 any more. With an RS version soon to be unveiled, production of the first motorsport-derived 991 is all but finished, and buyers who’ve left it this long to secure one must now scour Porsche’s dealer stock for pre-registrations and nearly new examples. Which don’t come cheap, by the way. 

The wave of positive press coverage that the GT3 has enjoyed has coincided with a winding up of supply that’s clearly surprised many and has resulted in prices rising beyond £140,000. In the way it so often does, the market has endowed this very special Porsche with a price to better reflect its spectacular abilities.

The first of which comes courtesy of what’s sitting immediately behind the rear axle. The GT3’s 3.8-litre flat six is its crowning glory. The forged aluminium and titanium internals and rocker arm valve train ring and clatter to make it sound as though the engine is chewing itself to pieces as you gradually let it warm through. It also uses plenty of oil, although the trip computer will politely tell you when it needs a top-up.

But all is forgotten when it’s on song and spinning through its incredible repertoire. Response is diamond sharp, power delivery building from urgent to dramatic as the tacho needle sweeps from 4000rpm towards 6000rpm. Above 6000rpm, it’s downright astonishing, matched on furious sense of occasion by only a handful of the very finest performance engines in the world, and vastly more dazzling than what the softer-edged GTS’s 3.8 can serve up.

And it’s fast – untouchable in this company. The turn of speed that the GT3 can put on feels much more savage than its headline power output suggests. On the road, by the time you’ve sampled 8000rpm in second gear, the temptation to drink it all in again in third may be more than your driving licence can stand.

Read the full 911 GT3 review

The GTS is a fast sports car, sure – moreover, a fast 911. Its performance is as remarkable for operational range and woofling, velvety texture as it is for outright pace. But if you’re looking at the apparently insignificant 28bhp per tonne difference between the two cars and betting that they can’t feel that different under your right foot, you’d be amazed by the difference in actuality. It’s stark – much bigger, say, than the previous Ford Focus RS was compared with the equivalent ST.

There again, you may be inclined to think: “So what?” What good is 468bhp if you can’t really use it on the road? But follow that argument to its logical conclusion and you don’t end up with a rationale to buy a 424bhp, £91k 911 GTS, but its little namesake.

The 335bhp Cayman GTS has one less gear ratio than the 911 GTS but gives up less to the newcomer on torque than power. It’s no giant-killer on pace, belonging in a lower performance division than either of its siblings. But the truth is that the performance the Cayman lacks isn’t really performance you miss. Not on the road, at least. Not if you value your liberty.

It’s intoxicating to indulge in the farther reaches of the 911 GTS’s rev range every now and again – and almost hallucinogenic to do so in the GT3. The Cayman’s 3.4-litre flat six doesn’t come alive above 6500rpm in quite the same way, balanced as it is more for mid-range muscle than redline hysterics.

But that bias allows it to keep up with its rear-engined betters as you howl along a steep and deserted B-road. It hits full stride sooner as you sweep out of corners and down short open stretches. And in reality, other than at the kind of lick and on the sorts of road that simply don’t figure in the UK, the Cayman GTS won’t be shrugged off the back of this 1200bhp Porsche cavalcade. Not for a moment.

The Cayman has what feels like a generous, road-appropriate power level. It also has the word-perfect answer to a question that must be posed on a regular basis at the chassis development ‘blue sky’ meetings of car makers the world over: “How should our new sports car handle?” The Cayman’s reply is brilliant. It isn’t contrived or complex. The car simply makes itself invisible; its driveshafts, suspension springs, brake calipers and contact patches are an instant and unconscious extension of you. It’s a trick not even the GT3 can pull off.

There’s no working this car out and little need to build trust, when every flick of the steering gives you sublime directional response and supreme confidence in the remaining grip level. The Cayman GTS tucks in to a greasy apex as though cornering was its natural state – like you’d imagine an old American stock car on staggered wheels and cross-weighted springs must have felt. Except so light and spry, and supremely eager.

If anything, you can criticise it for too much incisiveness at times – too great a readiness to change direction. The Cayman’s a softer-sprung car than either 911 because it can be. Its masses are more easily controlled by the suspension because they’re carried where they ought to be: between the axles. Softer chassis settings and a favourable weight distribution make the car corner with beautiful poise – but also flirt with roll-related oversteer if you carry too much speed or time your braking badly. It’s nothing the stability control can’t subtly deal with and presents itself more often on track than road. But it’s there, the inevitable consequence of true, pin-sharp chassis balance. And it means that, now and again, the Cayman’s driver might have a snatch of a throttle-off tail slide to focus the mind.

Lift-off oversteer is a dynamic character flaw that’s been studiously and successfully engineered out of the 911 over several decades. To the point where, on a slippery road bordered by rocks on one side and 100ft of fresh air on the other, your focus is entirely on the front wheels of this enigmatic, enduring sports car – whether GTS or GT3.

Putting a sports car exactly where you want it is, after all, the heart and soul of rewarding road driving. Doing that in the GT3 is a much easier and more direct task than in the GTS, because most of the time – even on wintry roads and at sub-5deg C – the GT3’s grip and steering response are leagues better. And that’s not all that marks its pre-eminence.

Although it’s stiffer than the GTS and less compliant at low speeds and suffers with more tyre noise, the GT3 actually rides better than its new range mate most of the time. It has that delicate initial damper response which begins to take the sting out of a bump the split second it impacts the suspension. The GTS’s adaptive dampers allow more compliance and initial suspension travel, only to intervene to check body movement once it has been allowed to develop. Very few sports cars could make the 911 GTS feel at all sloppy, soft or clumsy, but the GT3 is one of them.

The 911 GTS has similar weight in its steering to the Cayman but can’t match it on directional response. The GT3 gets closer, and it communicates feedback from its front tyres even better than the Cayman. But neither 911 goes around a corner with the telepathic precision of the Cayman.

Read the full Porsche Cayman GTS

Working the weight distribution of the bigger pair of Porsches, adapting your driving style around them and teasing the poise and precision out is one of the 911 driver’s lasting rewards.

In the stunningly immersive GT3 particularly, that occupation might sustain your interest for longer than either of the other two can manage.

But here’s the difference. In the GT3 – and, in a less grippy and precise sense, in the GTS, too – you probe away with the steering wheel, feeling for purchase and building belief in the car’s handling and eventually finding some.

In the Cayman, on the road, that belief is immutable and absolute – and the car is never more than three inches from where you pointed it.

The verdict

So where does that leave the new 911 Carrera GTS? No man’s land? Not quite. Even though it’s comprehensively outhandled by the Cayman on the road, greater performance and motive character mean it isn’t outpointed. And even though it fails to get close to the thrill of a GT3, it offers enough relative civility and usability to earn its place.

The truth is that you suspect the ‘GTS’ badge will be applied by Porsche more like a fairly ordinary trim level than a mark of real sporting flavour in the years to come.

This example feels like an optimally configured but familiar Carrera S, rather than anything genuinely new.

Does that make it one of Porsche’s all-time greats? No. But it’s a fine example of a sporting institution known and loved by so many – and for very good reasons. 

Read Autocar's previous comparison - New Lexus RC F versus BMW M4 and Audi RS5

Porsche 911 GTS

Price £91,098; Engine 6 cylinders, horizontal, 3800cc, petrol; Power 424bhp at 7500rpm; Torque 325lb ft at 5750rpm; Gearbox 7-spd manual; Kerb weight 1500kg; Top speed 190mph; 0-62mph 4.4sec; Economy 29.7mpg; CO2/tax band 223g/km

Porsche 911 GT3

Price £100,540; Engine 6 cylinders horizontally opposed, 3799cc, petrol; Power 468bhp at 8250rpm; Torque 325lb ft at 6250rpm; Gearbox 7-spd dual-clutch auto; Kerb weight 1505kg; Top speed 196mph; 0-62mph 3.5sec; Economy 23.0mpg; CO2/tax band 289g/km

Porsche Cayman GTS

Price £55,397; Engine 6 cylinders horizontally opposed, 3436cc, petrol; Power 335bhp at 7400rpm; Torque 280lb ft at 4750-5800rpm; Gearbox 6-spd manual; Kerb weight 1420kg; Top speed 177mph; 0-62mph 4.6sec; Economy 31.4mpg; CO2/tax band 211g/km