Cayman GT4: Where are we up to now?

[Motorhead]

There has been endless chatter on the forums about this car (P-9, Rennlist and our own Are Spyders....? endless post on the Boxster forum), so I though that it's about time we had something here, where it should be.

Firstly, the GT4 definitely is a done deal since it popped up very briefly on the US Porsche Driving Experience website [ http://www.planet-9.com/gallery/files/3/caymangt4confirmed_original.jpg ].

Secondly, there have been a number of sightings of the car [ http://www.autoexpress.co.uk/porsche/cayman/87008/porsche-cayman-gt4-spied-pictures ].

Speculation has it that it'll probably be announced officially at the 2015 Geneva Show but there'll be plenty of info "leaked" before then of course.

As far as the spec is concerned, from the pics it's obvious that there are a number aero mods compared with the basic spec 981s and the car appears to be running (lightweight?) bespoke 20" wheels and larger brakes with, perhaps, 6-pot callipers (carried over from the 991 GT3 parts bin?). Naturally, the lowered suspension set-up will be bespoke and I reckon that both manual and PDK 'boxes will be offered, but whether or not the latter will feature tweaked software (like that in the GT3) remains to be seen; the same applies to mods to the steering software.

There haven't yet been any interior shots but it's likely that it'll follow that of the Cayman R in having lightweight bucket seats, lighter door trims and fascia and radio and aircon delete options, although it's difficult to see where else Porsche can eliminate weight, other than to take out sound deadening material, owing to the aluminium construction of the BIW. Maybe there'll be a Clubsport package featuring a lightweight battery and smaller fuel tank options as well as a roll cage plus other race-oriented options for those who want to enter the GT4 Race Series.

The main bone of contention appears to be the engine and its power output. These have ranged from a 380PS (375BHP) tuned 3.4L up to it possibly being a 450hp turbo-4 or maybe fitted with the 981 GT3 engine (the latter two being totally far fetched in my opinion). There is also speculation that it will be a bespoke 3.6L version of the flat-6, but I can't see why Porsche would introduce an additional bore size when they've already got three capacities: 2.7L, 3.4L and 3.8L. Speculation has it that the 991.2 will have turbocharged flat-6s of 2.9L and 3.8L capacities, and if future Cayman and Boxster models are to feature the turbo flat-4 then it would be sensible for Porsche to have a single capacity flat-6 of 3.8L for the GT3, GT4(?) and the Turbo. So my take on it is that the GT4 will have a detuned 3.8L with a power output of 380PS which will give an improvement in low speed torque over the 3.4L. The detune will most likely come from throttle body/plenum revisions and a DME remap; the exhaust system will of course be bespoke, with lower backpressure than that in the standard cars.

Finally, the price. Hopefully it'll hit the showrooms at around £65k, but maybe that's just wishful thinking on my part as well as there being some garish colours - orange and green perhaps.

Jeff

 

[flat6]

Good on ya for posting this in it's rightful place. Will be interesting to hear what the Cayman clan think about it. As you say it's been discussed a bit in the Spyder 'corner' but with half a view as to whether a Spyder will follow suit. Would be interested to hear if people would plan to race this car or look to it for having a swifter, rawer Cayman for road and track days.

 

[Charlie_McLaughlin]

I have to admit to having placed a small desosit down on one..... and I wasn't even the first one at my OPC. However I need to see the spec etc , before convincing myself it will be better than my 997.1 GT3... Regards Charlie

 

[Motorhead]

Good on you Charlie. I'm sure that you won't be disappointed when the GT4 finally arrives. You may well be able to do a straight swop with your GT3 and still have a few quid in hand for some [expensive] Porsche options. How many on your PC's list; and do you have any idea yet about their likely allocation? Jeff

 

[ralphmusic]

Some random thoughts... It is not obvious to me whether a Cayman GT4 would be a special build version like the Aston N24 or a GT3-like road car as a basis for a GT4 race car. Looking at the list of currently eligible GT4 series cars (list below) it is a really broad church. Interestingly the 997 GT4 pictured racing on the series web site seems to be a Cup car so I suppose one can start with a "special" such as a 997 Cup and Ginetta or (very) road car such as an Audi RS5. The 997 is shown as 1411 kg and 3.4 kg/hp versus the Ginetta which weighs 1010 kg and 2.97 kg/hp; Porky by name and porky by nature.... I don't think the 3.4L engine will be suitable for the race series, it lacks torque. So I would think the 3.8L more likely; power can be determined by the ECU tune so we can all guess. I imagine the race gearbox will be a standard sequential so I can't see why any road version would not have a manual/PDK choice. I would hope the road car wheels would be 5 lug rather than centre locks, less cost to fit and maintain. The good thing about the Cayman platform is that it is pretty neutral, although it will rotate quickly being mid-engine. I can get 138 speedo mph just before braking into Woodcote at Goodwood and the same at Silverstone before Stowe. I think this talks to corner exit from Lavant onto the straight at Goodwood versus a power deficit limiting speed on a longer straight at Silverstone. They will no doubt fit better brakes for a track focused road car. However I run standard discs, pads and fluid and I still out brake most all but race type cars (maybe others don't try hard enough) and do not get fade over 15 - 20 minutes runs. My 981S weighs 1428kg and has electric memory seats, motorised lights, mirrors, etc etc so I would guess up to 100kg could be removed without making it uninhabitable. So if a weight/power target was 3kg/hp,1300kg would need 433hp and 1200kg would need 400hp. Power to weight looks no problem, but how much power can the platform take without really serious mods to suspension? If it is announced at Geneva in early March, how does that allow time for homologation for the GT4 Euro Race Series? Maybe road version 2015 and part year entry into race series pre full fat 2016? Currently listed 2014 eligible cars: Aston Martin Vantage N24 Aston Martin Vantage GT4 Audi RS5 BMW M3 GT4 BMW Z4 Corvette C6 Chevrolet Camaro Ford Mustang FR500GT4 Ginetta G50 GT4 Maserati Gran Turismo MC Maserati Trofeo Mazda MX5 Nissan 350Z Nissan 370Z Porsche 997 GT4 Porsche Cayman Lotus Evora Honda CR-Z Toyota GT86 GT4

 

[Motorhead]

Just a few points Ralph. The GT4 Race Series doesn't allow many mods to the standard car and sequential gearboxes aren't allowed (the cars must use stock gearboxes, although the PDK would need a dispensation since it's 7-speed), the idea being to make it relatively cheap to run a car in the Series. FYI here are the technical regs : http://gt4series.com/wp-content/uploads/2014/03/GT4-European-Series-Technical-Regulations-2014-1.pdf If it's running something approaching GT3 spec brakes, they should be more than adequate to cope with track use. I'm not sure that we'll see a Cayman GT4 running in the 2015 European Race Series - but we can always hope. With luck, Porsche will get behind some private entrants to get the cars competitive ASAP. From the pics, I don't think that the proto car is running centre locks [thank goodness!]. Jeff

 

[ralphmusic]

Jeff, I take your point on gearboxes except that Ginetta is sequential although an original fitment ( http://www.ginetta.com/cars_gt4) and I guess has a dispensation and I imagine the 997 GT4 runs a sequential Cup box.

 

[Motorhead]

Yes, as you say Ralph, the Ginetta G50 does have a 6-speed sequential box fitted as standard in GT4 spec, so presumably that's how they get away with it via the dispensation clause. But they're a very small, specialist outfit and I can't somehow see Porsche specifying a sequential 'box for the GT4 since it would take a lot of re-engineering. So it's more likely that the teams will have to use the 6-speed manual 'box or maybe take a punt on a [sanctioned] 7-speed PDK 'box. Although it's available, I can't see how the 997 GT4 would be allowed to run a sequential 'box under the current regs. Let's hope that Porsche are really serious about making the GT4 successful in the Euro Race Series and put in the appropriate investment. Jeff

 

[ralphmusic]

Hi Jeff, Looking at the various cars, some are motorsport team built specials. The 997 is a Cup car (sequential gearbox since 2007) with a conversion.... "GT3.nl is now taking orders for the conversion kit which makes the Porsche Carrera Cup and Porsche Supercup cars from 2007, 2008 and 2009 eligible for GT4 racing" http://www.gt3.nl/GT4-menu.pdf The Camaro seems to be a special build and has a Sadev 6 speed sequential an example in the advert below.. http://racecarsdirect.com/listing/45500/2x_chevrolet_camaro_gt4.html Of the 'standard' cars, the Aston has a Graziano six speed Sportshift (ASM), however the BMW which €123.5k + VAT has manual http://www.bmw-motorsport.com/dam/bmw/sportsmarketing/PDF/BMW_KS_ComM_110822_M3GT4-Vermarktung-Teams-en_dra_SoJ.PDF I would guess Porsche would go the BMW route with a track version (think Cup not RS) of a road car, but what would that car be? The list of BMW's specification differences may give a clue. Would Porsche produce a 3.4L Cayman above the GTS performance level and modify it as BMW have, or produce a more powerful 3.8L Cayman to modify. This latter approach seems more likely and is a scenario that supports Weissach being responsible for delivering race GT4s as they do for Cup cars. This would leave Porsche with an issue of using a 6 speed manual gearbox when sequential has generally replaced manual in pretty well every race category and a majority of GT4 vehicles have it. Perhaps they would talk with BMW and get regs changed? My guess, 3.8L road car with manual and PDK - why ever not as all the systems support these, Motorsport prepared 3.8L race cars with dispensation for same sequential as in 991 Cup cars. Prices, race cars let's say as BMW at €123.5k + VAT, UK spec road car without deviating stitching and other essential options maybe a little below £70k. Ralph

 

[Motorhead]

Well done for sourcing that info Ralph. On the face of it, it looks as though a proverbial bus has been driven through the regs regarding the choice of gearbox, but I suppose that at the end of the day, the regs are there to be "interpreted". However, I thought that the whole idea of GT4 was to keep the cars close to road spec to keep complexity and costs down. As said in my OP, I'm with you in thinking that Porsche will go with a 3.8L manual and PDK as a base road car. Because of it's mid-engine layout, the GT4 would need a different sequential 'box from that installed in the 991 Cup cars, but I'm sure that something is available [the Hewland 'box as fitted in the Ginetta perhaps] provided a dispensation is allowed. Jeff

 

[Motorhead]

Just picking up on some other points you've made Ralph. Looking at the 2014 Euro Series results, the Ginetta G50 appears to be the car of choice [no doubt due in part to its superior power/weight ratio and race-focused set-up], but the BMW M3 features strongly even though it's running a manual 'box and tips the scales at 1380kg but with a decent 420hp. Strong support from BMW Motorsport though and if Porsche were to give similar support for the Cayman, a 380~400hp 1300kg car with manual 'box could be a potential challenger with a bit of development. Jeff

 

[clubsport]

What evidence is there that this won't be just a nicely specced and upgraded GTS with a Gt4 badge on the back? I have not been able to find anything to conform (as yet) this will be a homologation special. Sadly the differential between the road and track versions is far wider in the current environment compared to the days of the air cooled cars.

 

[Motorhead]

Pure speculation of course Paul. We don't yet know the spec for the road-going version. And you're right in saying that, unfortunately, these days there seems to be an ever increasing gap between road and track versions of the cars. As I understand it, the whole purpose of GT4 is to make the cost of racing in this category about a third of that for the GT3 formula by restricting modifications to the cars, these supposedly being "track-day specials" suitable for both private entrants as well as race teams. Whether or not this goal is being achieved is perhaps open to question, although the fact that BMW are offering a race-ready car for less than £120k does indicate its potential affordability. It's also an opportunity for Porsche to put another part of the marque up against market competitors such as Aston, Audi, BMW, Maserati, Lotus, etc., rather than relying solely on the 911; and that can't be a bad thing in my opinion. Jeff

 

[Chris_in_the_UK]

Thanks for the thread Jeff. Much speculation and nothing certain as yet. My 'crystal ball' (Lol!) suggests...... 1. The rear wing will change for the production car. 2. PDK only. 3. Lots of 'lightweight' stuff similar to the Cayman R - seats, door pulls, panels etc. 4. It WILL NOT usurp any perceived equivalent 911 in the current range in terms of performance. For this alone, I would not be interested. 5. It WILL look the 'dogs' and for real drivers it will be the car to have out of the range.

 

[clubsport]

Motorhead, I appreciate the Gt4 formula, the prospect of Porsche bringing a true trackday / semi competitive car in for £60-70k seems unlikely to me. I really do think this car is going to be a "tribute" in the way the Cayman R was. Lets wait and see, either way no doubt it will be a great drive and possibly the best new enthusiast Porsche available.

 

[flat6]

Will be interesting to see whether it's more road or race. The road going GT3 doesn't have a sequential box option (thinking of 997 & 996, 991 is nothing like the race car). You'd have to buy the Cup car? (I think, haven't checked). So are you guys talking of 2 separate versions of Cayman GT4, road and race versions? Or are you saying you'll be able to option a sequential box onto a showroom model? I'm not quite following.

 

[MrDemon]

5th feb release date 65k 200 cars 3.6 375bhp Manual only. Just need the finer details, like packs ie a Clubspprt , brake and sus details. Car will be seen along side the 991RS as motor sport cars.

 

[flat6]

Is that 200 cars for UK or worldwide?

 

[spyderwhite]

ORIGINAL: MrDemon 5th feb release date 65k 200 cars 3.6 375bhp Manual only.

All speculation gleaned from other websites at the moment!

 

[Motorhead]

Many thanks for the comments chaps. Keep 'em coming. 6, I think that you have to distinguish between road and race cars. Most importantly, for the GT4 to be a commercial success the road [and occasional track-day] car probably has to have a price point around £65-70k with a spec something like that which I outlined in my OP. A Clubsport option, such as that offered for the GT3, would cater for the track-day enthusiast. There's no way in which Porsche would offer a sequential race gearbox for a "showroom" car - far too unrefined for road use. As BMW have shown with their GT4 M3, a Cayman GT4 race car could potentially be offered to race teams and private entrants for ~£120k by Porsche Weissach, although that would require a commitment of considerable resources. I'm sure I read somewhere that Porsche are struggling to shift GT3 Cup cars, so perhaps there's sufficient spare capacity in the Motorsport department to develop and supply a competitve Cayman GT4 race car. We can always hope..! Jeff