997 GT3 RS 3.8 v 4.0
Total 911 fires up a fiery Mezger double act between two of the greatest-ever Rennsports to leave Weissach…
The last of the manual Rennsports do battle on closed roads to find out which offers the most scintillating drive
Rennsport: it’s a fabled and oh-so evocative Porsche designation that evokes a heady assemblage of truly unrelenting, motorsportderived excitement at the wheel of a sports car. Quite rightly, the ‘RS’ sits at the pinnacle of the
911 bloodline: it is the quintessence of automotive finesse in a road car, the rawest, purest instance of breathtaking performance on four wheels. And right now, I’m pedalling one of the best.
My hands are clasped to an Alcantara-lined steering wheel as I point the 997 GT3 RS toward London. In true RS style, the driving experience is best described as raw. There’s no radio or air conditioning in here and the source of all noise is behind me: thanks to a Perspex rear screen, the factory-fitted titanium exhaust resonates poetically back into the cabin at even gentle acceleration past 4,000rpm, and when that’s not engulfing my ears, rolling tyre noise from the huge 325 cross-section Michelin Pilot Sport Cups is doing the job. Naturally, I prefer the exhaust note.
Even on this fairly smooth blacktop, the GT3 RS’S ride is still firm. PASM (standard equipment here) is always selected when the engine is started, with switchable ‘Sport PASM’ providing shock-absorber tuning for what Porsche describes as ‘high driving dynamics’. That’s not needed just yet, but the variable suspension system nevertheless selects the appropriate damping level for each individual wheel according to a variety of parameters and conditions. It’s the same policy for the GT3 RS’S engine mounts with variable damping (PADM), which ranges between an almost rigid setting and a decoupling of sorts of engine from body.
As a result, every permissible camber and crevice in the road is keenly felt; even running over cat’s eyes when changing lanes throws up a distinct ‘bump and shudder’ body sensation normally only encountered in classic 911s. As you can see, then, everything about the 3.8-litre GT3 RS’S chassis is geared for the race track, and so is the performance. As a result, on the public road I’m constantly having to short shift through the Rennsport’s six forward gears to try and keep on the legal side of the maximum 70 miles per hour speed limit. It’s as frustrating as it is tantalising: this GT3 RS is teasing me as to its performance credentials and, akin to a fly to a light, I have to be explicit in resisting the overwhelming urge to plant my right foot to the floor and watch the tacho needle swing all the way round to the redline, at least until these semi-slick Michelins are rolling over the asphalt of the proving ground later in the day. First though, I’ve a rendezvous in north London to meet an RS 4.0.
Widely considered as the greatest Porsche to grace the public road, the RS 4.0 project was borne out of a surplus of 997 GT3 RS parts and a desire from Weissach to reward only its most loyal of
GT3 customers with a special car that pushed the capabilities of the famous Mezger engine to its very zenith, all in the quest for ultimate performance driving. Priced at £128,000, Porsche made no profit from each of the 600 RS 4.0s made. It was based on the already breathtaking 3.8-litre 997 GT3 RS, though a number of revisions were bestowed upon the RS
4.0 across its engine, chassis and aerodynamics.
The engine is derived from Weissach’s GT3 R race car, increasing the stroke in the 3.8 GT3 RS from
76.4 to 80.4 millimetres. The chassis has rosejointed rear suspension arms with helper springs for the unsprung mass, and the RS 4.0’s downforce is improved at the front thanks to dive planes channelling air up and over the front corners, while the thicker rear spoiler has a natural angle of nine degrees instead of the 3.8-litre Rennsport’s six. Additional weight saving has taken place with plastic screens from the B-pillar back (the rear quarter panels in the 3.8 are glass), while the front bonnet consists of little more than a carbon-fibre composite with a smattering of paint and a stickered-on Porsche emblem rather than the metal crest atop the alloy bonnet of the 3.8.
This delightfully meticulous assortment of tweaks makes for fascinating reading, but a glance at the performance statistics suggests only minimalist gains. Top speed in the RS 4.0 is only increased by one mile per hour to 193 compared to the 3.8, while just 0.1 of a second is shaved off the 0-62 miles per hour dash. But as ever with Porsche and Weissach in particular, the magic isn’t solely in the performance times, but in the mechanical details that help instigate them. The RS 4.0 is the ultimate in this, as I’m about to find out.
Arriving at the premises in Hendon where this particular RS 4.0 resides, I get my first glimpse of the famous white bodywork of Porsche’s ultimate
911 Rennsport. I am utterly starstruck. Pulling up behind the huge rear wing (sitting on taller supports) my feeling of excitement quickly transcends into veritable awe. It’s as if an international rock star has entered the vicinity: take Slash of Guns n’ Roses fame, for example, casually rolling on set complete with that famous top hat, a lit cigarette hanging from his mouth, clutching his famous Gibson Les Paul, ready to rock in front of us.
Needless to say, it’s no great wrench to swap the cockpit of the RS 3.8 for that of the RS 4.0. Apart from the obvious note of the dashboard being flipped – this is a left-hand-drive example originally delivered to the principality of Monaco – there is much change. Packed with substantially more equipment than the comparatively spartan 3.8 GT3 RS, the utility of the RS 4.0’s interior is more wholesome in almost every category. Bizarrely though, this means while the 4.0 gains Schroth five-point harnesses as well as a comprehensive roll cage extending above the driver’s head and down the ‘A’ pillar, it also features air conditioning and PCM 3.0. So, what this cosmopolitan example lacks in sheer pared-back character, it more than makes up for in its ability to provide an accomplished drive for both road and track. Butzi would be proud.
En route to the proving ground, it doesn’t take long to acclimatise to the RS 4.0 (the 3.8-litre Rennsport I arrived in is being driven close behind). The clutch pedal is just as weighty as the 3.8 and the PCCBS will eventually let out their usual squeal under light braking in traffic, but there’s no doubt the RS 4.0 is useable on the public road, even if that rosejointed rear suspension makes the ride incredibly crashy over less-than-amiable road surfaces. So far,
“If the 4.0-litre is considered the king of kings, then the GT3 RS 3.8 is the people’s champion”
so good: Porsche generally hasn’t sacrificed usability in the hunt for performance.
However, it’s away from the public road where any 911 Rennsport can really exert its excellence, a sentiment to be echoed here by both the brilliant
3.8 and 4.0-litre 997 GT3 RSS at Longcross Proving Ground. With warm tyres – pressures aren’t changed here to complement the ‘fast road’ chassis setup of both examples on test – I jump back in the 3.8-litre GT3 RS and take to the ‘Snake Pit’, a fast yet twisty stretch of wide, smooth asphalt with sweeping corners that vary in length, angle and elevation. It is the ultimate test of any car’s chassis.
Heading down the flat straight before turn one, I finally get to bury the accelerator pedal into the floor and the GT3 RS 3.8 responds by shooting forwards mercilessly. I eventually turn in hard in third gear, coming off the gas to allow the front to tuck in for the apex. The steering feel and weight is simply tremendous, possibly the best I’ve encountered in a 911: the car responds expertly and immediately to every minute adjustment I make at the wheel in searching for that perfect line, and the chassis retains its composure through the long corner as the Michelins dig in hard for grip. The GT3 RS feels so incredibly lithe from the rear (aided by those active engine mounts, no doubt) and the scream of the Mezger engine as I exit the corner and get back on the loud pedal really has my hair on end. This is absolutely exhilarating.
Pushing hard through this succession of corners for the next half hour or so, one or two things become apparent with the 3.8. First, it’s actually very easy to drive on or near the limit. The more you push, the more you can feel the GT3 RS hunkering down to the road surface, the extreme aerodynamic styling proving it is no gimmick. However, the front end can still feel a little vague when pitching in for a turn, which is a 911 idiosyncrasy that is perhaps amplified here in the midst of such an otherwise exemplary driving machine.
Piloting the 997 GT3 RS 4.0 through the same bends throws up a surprisingly different experience, so much so that I’m taken aback by the starkness of it. The additional torque in the RS 4.0 is immediately noticeable: where the 3.8 flat six’s typically peaky nature means you have to work hard to exhume the full thrust of its audacious power (it really gets going past 4,000rpm), the RS 4.0 is quicker to get shifting, with peak torque arriving some 1,000rpm sooner, or at 5,750 compared to 6,750rpm in the 3.8.
Though the 3.8-litre GT3 RS isn’t slow by any stretch, the RS 4.0 is one of the fastest naturally aspirated 911s there is (without launch control) to a degree that its low-down torque feels almost unlike a 911. This means that corners are sometimes tackled in different gears in the RS 4.0 – the beautiful short-shift gearbox is the same as the 3.8-litre variant, complete with 13 per cent shorter ratios than that of the 997.2 GT3 – though the caveat to the extra torque available means you must be wary of getting on the power too early when exiting a corner in the RS 4.0.
Even the sounds emitted from both boxer engines are altered: if the engine rumble of the 3.8-litre GT3 RS is comparable to a throaty bark, the RS 4.0 is more akin to a meaty growl, so different is the tone. There’s also a heightened induction noise in the RS 4.0. Though I’ve spent the previous week marvelling at the audible induction gasp in the 997 GT3 RS 3.8 thanks to its Perspex rear window and removal of sound deadening, the same gasp under acceleration in the RS 4.0 is more pronounced. I put this down to the removal of double-flow air filter housings in favour of larger conical items in the 4.0.
An excessively stiff chassis displayed earlier by the RS 4.0 on road is converted handsomely on the proving ground too, helping the car settle quicker into a corner while the additional aero tweaks at the front and rear help it hunker down to the floor with up to 190 kilograms of downforce behind it. As a result, the RS 4.0’s svelte style as it carves through all manner of corners and straights and cambers and flats is simply enchanting.
It is obvious that both 997s are scintillating modern Rennsports. As you’d expect, there’s plenty of feedback constantly relayed from the identical Pilot Sport Cups, allowing you to really lean against their limit when cornering fast. The sensation is like racing a Cup car. Even better, these 997s still have an abundance of that classic 911 trait where the driver is able to pivot, mid-corner, from the back of the car using the accelerator pedal, a feeling the more midengined 991 iteration lacks.
So, how to place these two exquisitely scintillating 911 GT3 RSS? Well, the 4.0-litre is sheer Rennsport royalty, the king of kings with breathtaking performance, boasting the biggest Mezger-derived engine sitting in the back for good measure. Typically undervalued by Porsche on its release, the RS 4.0’s stock has risen so significantly in its short life that acquiring one today would have a greater impact on your bank balance than a suburban three-bedroom semi, a phenomenal achievement for a modern-day 911 just a decade old.
But if the 4.0-litre is the regal GT3 Rennsport, then the 3.8 is the people’s champion. While the RS 4.0 is buoyed by its limited production run of just 600, a 3.8-litre build run of some 1,500 examples means they are significantly less rare, with reciprocating values lower at around £130,000. This means that, most importantly, these Rennsports are more likely to still be regularly driven – and hard.
Whatever your preference may be, the last two 997s added to the GT3 RS heredity are sensational, and though the subsequent 991s may be more precise, for me this truly is the benchmark in pure analogue 911 exhilaration.