718 Cayman GT4 is here – at long last.!
- Thread starter Motorhead
- Start date
Twinfan said:
The 4.0L engine features (numerous posts ago) will provide a far better platform for meeting standards but the engines will be running very lean under all load conditions (lambda 1 has been reported) and current intake and exhaust configurations will require significant change. In addition I suspect it will require new ECUs and maybe a very significant restructuring of the programming.
And as for AP, to quote Mandy Rice Davies he would say that wouldn’t he. Euro 7 is still being negotiated and given Porsche‘s tribulations with GPF, I wouldn’t bet on anything.
Motorhead said:
Neither am I but prospective German owners are reporting CoC delays, or rather delays attributed to CoC. Perhaps there is an introduction to manufacture audit or review element to the CoC but the same reason was given for delays recently in releasing GT3RS models.
Talking with my local Centre Principal, he says getting good build and delivery data from the factory is very difficult with dates changing randomly.
Here is a link to an article discussing future emissions targets and how they might be achieved. It starts with the core lambda = 1 challenge, and seeks to suggest how a very high output level of 200kW/L might be met, presumably to test by looking at extremes given ever tightening regs. For interest, the 992 Carrera S produces 331kW out of 3 litres. Not so sure normal aspiration works here.
992 S co2 emissions are 205 gm/km 3 litre turbo 331kW
718 GT4 # are 249 gm/km 4 litre normally aspirated 309kW
http://magazine.fev.com/en/200-kw-l-at-lambda-1/
992 S co2 emissions are 205 gm/km 3 litre turbo 331kW
718 GT4 # are 249 gm/km 4 litre normally aspirated 309kW
http://magazine.fev.com/en/200-kw-l-at-lambda-1/
Ralph,
That article makes rather depressing reading for fans of naturally aspirated engines and explains why Porsche and other manufacturers are favouring the turbocharging route with maybe the Miller cycle (interesting to learn that lambda = 1 reduces the specific power of current n/a petrol engines to about 65 kW/litre).
Natural aspiration now appears to be confined to motorbikes, which appear to be subject to a less stringent emission control regime at the moment, although turbocharging seems to be coming on high-end bikes and all bikes have cats but not GPFs as yet. Oddly, I note that bikes aren't subject to an MOT emissions check despite some very large capacity multi-cylinder n/a engines being available - the Triumph Rocket III has a whopping 2294cc capacity..!
Jeff
That article makes rather depressing reading for fans of naturally aspirated engines and explains why Porsche and other manufacturers are favouring the turbocharging route with maybe the Miller cycle (interesting to learn that lambda = 1 reduces the specific power of current n/a petrol engines to about 65 kW/litre).
Natural aspiration now appears to be confined to motorbikes, which appear to be subject to a less stringent emission control regime at the moment, although turbocharging seems to be coming on high-end bikes and all bikes have cats but not GPFs as yet. Oddly, I note that bikes aren't subject to an MOT emissions check despite some very large capacity multi-cylinder n/a engines being available - the Triumph Rocket III has a whopping 2294cc capacity..!
Jeff
Jeff,
The future for interesting personal transport modules does not look good. Neither do the prospects for European auto manufacturers. The € billions being invested in electric propulsion will be wasted because few will buy the vehicles. They are too expensive, have a shorter operating life than IC, are unsuitable for use in most of the world’s land mass, and rely on enabling infrastructure which is all political ambition and little action, whilst better technologies are being ignored.
Going for a drive...
The future for interesting personal transport modules does not look good. Neither do the prospects for European auto manufacturers. The € billions being invested in electric propulsion will be wasted because few will buy the vehicles. They are too expensive, have a shorter operating life than IC, are unsuitable for use in most of the world’s land mass, and rely on enabling infrastructure which is all political ambition and little action, whilst better technologies are being ignored.
Going for a drive...
...and before I get in the car to drive, I should note that the 992 S numbers quoted in post #285 is PDK v manual in the 718 GT4. The latter engine being by today’s emissions standards uncompetitive and unimpressive so the prospect for performance enhancements may well be constrained by the need to comply with Euro 7, despite what AP asserts.
Nick_USA said:
The reference was to release to customers of cars at dealers, not build
ralphmusic said:
ralphmusic said:
Agreed on both counts Ralph. Manufacturers seem to be fixated on heading down the BEV route - with all the associated and well-publicised infrastructure problems - when there are other alternatives, hydrogen propulsion being among them where the service station model we have currently would be a better infrastructure fit, and such stations already cater for the storage of highly volatile fuels. Granted, hydrogen generation would be electric power intensive but the low emissions BEV model assumes the use of sustainably generated electricity. I think that even the Chinese are looking very carefully at putting significant funding into the development of hydrogen rather than battery powered vehicles.
As a lifelong car enthusiast I find it rather depressing but I can see that in the not too distant future when autonomous vehicles are the norm the need for personal transport could well disappear, to be replaced by taxis and buses for shorter journeys and trains and aircraft for longer journeys. A Utopian view perhaps, but anything's possible as our roads become more and more congested.
Jeff
Jeff,
https://twitter.com/gregkable/status/1167818796549255168?s=21
Since Xi Jimping’s vist to Toyota a year plus ago, no new Chinese state development grants have been given for automotive battery power, almost all on hydrogen cell development.
https://twitter.com/gregkable/status/1167818796549255168?s=21
Since Xi Jimping’s vist to Toyota a year plus ago, no new Chinese state development grants have been given for automotive battery power, almost all on hydrogen cell development.
...and the Toyota plant Xi Jinping visited
https://twitter.com/toyotauk/status/1168897830972469253?s=21
https://twitter.com/toyotauk/status/1168897830972469253?s=21
..enough of the future, aside from an RS of course. Anyone got one or been on PEC in one yet?
Have you looked at how few Hydrogen fuelling stations there are in the UK ?
And all are slated to use local power to generate local Hydrogen at high pressure ... eyes widen.
To be honest, the Chinese steal so much technology that the smart operator would show them precisely the wrong way to go.
As for Ev, has anyone calculated how much extra Ev capacity would be required to supply a serious percentage of fossil fuel conversion ?
The Classics are looking increasingly interesting ... and they don't make them anymore so nobody can over-supply the market.
My thoughts ... most people need more than one car in order to satisfy the Eco Warrior in them and have fun on high days and fundays.
BUT ... I am having as much fun with a lovely '71 Morris Minor 1000 as I am with my "89 3.2 Jubilee ... each to their own.
Depressed ? I feel so lucky to have lived through the last 50 years where the only way was up ... and there appeared to be no need to self flagellate.
That isn't to say that I ever wasted ... but at least I felt able to enjoy what made me happy.
And all are slated to use local power to generate local Hydrogen at high pressure ... eyes widen.
To be honest, the Chinese steal so much technology that the smart operator would show them precisely the wrong way to go.
As for Ev, has anyone calculated how much extra Ev capacity would be required to supply a serious percentage of fossil fuel conversion ?
The Classics are looking increasingly interesting ... and they don't make them anymore so nobody can over-supply the market.
My thoughts ... most people need more than one car in order to satisfy the Eco Warrior in them and have fun on high days and fundays.
BUT ... I am having as much fun with a lovely '71 Morris Minor 1000 as I am with my "89 3.2 Jubilee ... each to their own.
Depressed ? I feel so lucky to have lived through the last 50 years where the only way was up ... and there appeared to be no need to self flagellate.
That isn't to say that I ever wasted ... but at least I felt able to enjoy what made me happy.
ralphmusic said:
I think one chap on here has a PEC booking for November and someone on PH had a drive of the latest GT4 this week. Compared with his 981 GT4 he reckoned that, given the limitations of the PEC track, overall it was an incremental step up but that the new engine was much stronger at the top end. Here's his review:
Well. I’ve driven it.
The one at PEC is the yellow pre production vehicle they had at Goodwood. This is obviously my opinion only, but I did have a very good squirt in my 981 GT4 at the weekend to make as good a comparison as I could.... First off, obviously, from outside it is much quieter. Inside however, with the exhaust valves open it is just as loud, albeit a very different noise. It’s a smoother sounding engine, but with a deeper growl as the revs rise. Virtually no overrun burble now, but overall I was pleased. I’m sure this will be a little more subdued sounding at light throttle/slower speeds. Handling has improved. It’s better balanced somehow and seems to settle out in corners when pushed even better than the 981. Turn in is noticeably sharper, which is saying something as the last one wasn’t exactly sluggish. Just seems even more chuckable and “darty” to me. Engine.......is in my opinion fantastic. It pulls hard all the way to 8k, whereas my 981 starts to get out of steam over 6500rpm. You can definitely feel the extra power, but at PEC you never really get up to high enough speeds to really feel the difference. Excited to get the 718 onto a proper track. The other noticeable step on is the extra torque really pulls it out of slower corners and makes a big difference. This definitely helps make the longer gearing feel that bit better, but I’ve never personally had much issue with the gearing anyway. Clutch is lighter, but that is good news for my sciatic nerve! Steering felt as well weighted to me. Overall feels like it’s just moved up a notch, definite evolution but not night and day. I’m excited to get mine and really enjoy it.
Jeff
ChrisW said:
Best comment in ages....
Brian_Innes
Member
ralphmusic said:
I couldn't agree more.......
Brian
They're a bit late to the party but here's PH's take on the GT4 RS.
https://www.pistonheads.com/news/ph-porsche/porsche-cayman-gt4-rs-set-for-450hp/40988
450hp engine with internals borrowed from the GT3 4.0L (questionable?); PDK only (almost certainly); race-derived brake cooling (obviously! -NACA ducts in the bonnet and louvres replacing the rear side windows) with PCCB; a £100k price tag (most probably, but spec dependent) ... and zero availability (a given).
Jeff
https://www.pistonheads.com/news/ph-porsche/porsche-cayman-gt4-rs-set-for-450hp/40988
450hp engine with internals borrowed from the GT3 4.0L (questionable?); PDK only (almost certainly); race-derived brake cooling (obviously! -NACA ducts in the bonnet and louvres replacing the rear side windows) with PCCB; a £100k price tag (most probably, but spec dependent) ... and zero availability (a given).
Jeff
Jeff,
I am sure they don’t need >8k revs for 450PS. I’d think the rear window openings would more likely either provide more engine cooling, or higher pressure feed for intake plenum, over brake cooling.
Ralph
I am sure they don’t need >8k revs for 450PS. I’d think the rear window openings would more likely either provide more engine cooling, or higher pressure feed for intake plenum, over brake cooling.
Ralph
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