718 Cayman GT4 is here – at long last.!
- Thread starter Motorhead
- Start date
Twinfan said:
Agree with Ralph, you will find the PEC 718 GT4 has a freer engine than the standard 981, it pulls all the way to 8000 and does not feel strangled which I used to find frustrating. Mine is still running in but it also has more low down which makes it a nicer road car. It does not sound as good but we all expected that. I think that there is also a noticeable improvement in both the steering and chassis. I'm sure you will have an enjoyable 1/2 day let us know your thoughts .
Jens reckons that the splined gearbox is good for 550 Nm --- which is well over 400 ft lbs. And used in the Audi V8's etc.
By comparison the old G50 box from the air-cooled era was said to be good for 500 Ft lbs.
Certainly the evidence from the tuned market would suggest that this is not unreasonable.
Maybe the later welded (second ?) gear is still a limiting factor ... defined by Porsche ?
I mean, why did they change ?
By comparison the old G50 box from the air-cooled era was said to be good for 500 Ft lbs.
Certainly the evidence from the tuned market would suggest that this is not unreasonable.
Maybe the later welded (second ?) gear is still a limiting factor ... defined by Porsche ?
I mean, why did they change ?
Chris,
I think your timeline is wrong.
Started splined, changed to welded by gearbox vendor, failures, reverted to splined, I assume vendor paid for replacements..
Ralph
I think your timeline is wrong.
Started splined, changed to welded by gearbox vendor, failures, reverted to splined, I assume vendor paid for replacements..
Ralph
Chaps,
I'm sure I read somewhere that the original gearbox/transaxle in the 986 was used in an Audi? I assume that it's been updated substantially since then by Getrag to Porsche's spec, and I'm sure that Porsche would have sanctioned the change from spline to weld too, so there were probably some interesting discussions between the two parties when the failures began! The torque spec would have incorporated a significant margin of safety, as witnessed by the fact that a significant number of "modders" have been running cars with substantially more power and torque than standard and haven't encountered problems, but then they're not worried about warranty claims.
Jeff
I'm sure I read somewhere that the original gearbox/transaxle in the 986 was used in an Audi? I assume that it's been updated substantially since then by Getrag to Porsche's spec, and I'm sure that Porsche would have sanctioned the change from spline to weld too, so there were probably some interesting discussions between the two parties when the failures began! The torque spec would have incorporated a significant margin of safety, as witnessed by the fact that a significant number of "modders" have been running cars with substantially more power and torque than standard and haven't encountered problems, but then they're not worried about warranty claims.
Jeff
ralphmusic said:
I'm not sure what timeline you are referring to, but if the welded gearbox reverted to splined I'm pleased to hear it.
I had asked if the replacement gearboxes were splined and nobody seemed to know. Now I do
G50 was the 915 replacement in the mid life 3.2 which was retained through 993RS and I believe into the GT3 with around 270 ft lbs. This possibly gives a measure of the robustness of these Gretag boxes when they were said at the time to be good for 500 ft lbs.
A thought, is one of the challenges for gearboxes now the extra grip available in the rest of the transmission ? Tyres / Clutch ?
A slipping tyre or clutch is great torque limiter ...
Jeff, having stepped completely outside the Porsche warranty "bind" it's great not to have worry about N rated tyres or branded batteries etc.
I no longer have my car serviced by the OPC --- I would find myself telling them not to touch things that my specialist dealer who massively over services the car for me, is happy to work with !
Of course I have all the original bits ... but I can't see anybody wanting to return my car to standard. Since modification my consumption of tyres and brake pads has plummeted as the composure and tactility of the car has soared ...
'Now back on track on the 6th March at the Oulton RS day running my non-N rated MPSS's for the cold and possibly wet !
I no longer have my car serviced by the OPC --- I would find myself telling them not to touch things that my specialist dealer who massively over services the car for me, is happy to work with !
Of course I have all the original bits ... but I can't see anybody wanting to return my car to standard. Since modification my consumption of tyres and brake pads has plummeted as the composure and tactility of the car has soared ...
'Now back on track on the 6th March at the Oulton RS day running my non-N rated MPSS's for the cold and possibly wet !
Looks as though the 718 could live on until 2024, but could well continue past 2026:
https://www.topgear.com/car-news/hurrah-porsches-40-flat-six-has-years-life-left-it
Jeff
https://www.topgear.com/car-news/hurrah-porsches-40-flat-six-has-years-life-left-it
Jeff
Interesting, but the 982 platform would be VERY old by then.
The comment that an electric 911 will come before a 718 is at odds with previous Porsche statements that the 911 would be the last to change. On that basis, either Porsche are feeding duff info or the article is clickbait.
The comment that an electric 911 will come before a 718 is at odds with previous Porsche statements that the 911 would be the last to change. On that basis, either Porsche are feeding duff info or the article is clickbait.
Agreed Dave - the 982 platform itself would be positively ancient by 2026, bearing in mind that it's just an updated 981 which was announced in 2012. Porsche would have to do some sort of update by then even if it just tinkered with the front and rear bumpers and maybe updated the dashboard à la the 992, although I would have thought that an electronic dash would be expensive to implement.
I think that the article is probably journalistic tosh. As you say, word from Porsche is that a full electric 911 is way off (even a hybrid is questionable at the moment) and it's more likely that they'll test the water first with the mid-engined cars. Maybe - like the Macan - they'll run ICE and electric cars in parallel if there's sufficient production capacity?
TG are saying that PDK won't be available until early 2021, although forum chat seems to indicate that September this year is the likely introduction date, so we'll have to wait and see. Unsurprisingly, it will be introduced simultaneously across the 982 F-6 range.
Jeff
I think that the article is probably journalistic tosh. As you say, word from Porsche is that a full electric 911 is way off (even a hybrid is questionable at the moment) and it's more likely that they'll test the water first with the mid-engined cars. Maybe - like the Macan - they'll run ICE and electric cars in parallel if there's sufficient production capacity?
TG are saying that PDK won't be available until early 2021, although forum chat seems to indicate that September this year is the likely introduction date, so we'll have to wait and see. Unsurprisingly, it will be introduced simultaneously across the 982 F-6 range.
Jeff
Yep, that's what I would expect. It'll be interesting to see where Porsche position the Cayster in the future. Currently, outside of the GT car program, the new 4.0 GTS is the only NA sports car you can buy.
I wonder if Porsche are testing the waters to gauge demand for such cars longer term?
I wonder if Porsche are testing the waters to gauge demand for such cars longer term?
With the Government bringing forward to 2035 the end of ICE car sales in the UK, who knows where we're going Dave? Although I'm sure there'll be a rush before that date to buy the last ICE cars, there's no indication from our esteemed leaders how long owners will be allowed to drive their cars or even how long fuel might be available to power them. The usual muddled thinking from politicians I'm afraid.
The definition of Porsche GT cars will have to change very rapidly because I'm sure that we'll be seeing the rest of the EU following the UK's lead, although who knows what will happen in Trumpland, a very important Porsche sports car market?
Jeff
The definition of Porsche GT cars will have to change very rapidly because I'm sure that we'll be seeing the rest of the EU following the UK's lead, although who knows what will happen in Trumpland, a very important Porsche sports car market?
Jeff
Brian_Innes
Member
ChrisW said:
Chris,
I couldn't agree more with your comments. We racers are a different breed where performance, aka speed and lap times, are EVERYTHING.
In my experience with servicing at OPC's I always tell them not to touch my suspension geometry. They are my settings and work perfectly.
Having enjoyed many passenger laps in your 981 GT4 both before and after modification, I can completely agree with your comment "I can't see anybody wanting to return the car to standard" Amen to that.
I shall also be attending the Oulton Park RS day and look forward to another demonstration of your superbly modified 981 GT4.
Brian
Back on the subject of 982 lifetime. The Euro 6-compliant 4.0L 9A2 Evo engine is good until January 2013, but it’s set to satisfy the incoming ‘AP’ legislation also. Frank Walliser (VP of 911 and 718 product lines) reckons:
“AP comes and has to be fulfilled…AP is the end of [Euro 6-DG-Temp], that should last until end of [20]23,” Walliser said, adding, “Then we hope for three years of silence, and then we expect a small improvement in the AP and then the next big move will come in [20]26, Euro 7.”
https://www.carthrottle.com/post/porsches-gt4gts-na-flat-six-will-stick-around-until-2026/
It sounds as though 2026 could be a watershed for pure naturally aspirated IC engined cars?
Jeff
“AP comes and has to be fulfilled…AP is the end of [Euro 6-DG-Temp], that should last until end of [20]23,” Walliser said, adding, “Then we hope for three years of silence, and then we expect a small improvement in the AP and then the next big move will come in [20]26, Euro 7.”
https://www.carthrottle.com/post/porsches-gt4gts-na-flat-six-will-stick-around-until-2026/
It sounds as though 2026 could be a watershed for pure naturally aspirated IC engined cars?
Jeff
I'm curious to see where else the 9A2 4.0 will be used. It was originally claimed to be a 982 platform engine only, but if it's sticking around and investment needs to be recouped will we see it in a 911? Even if it's 982 only, where else will we see it? Or will they just keep churning out the current GT4/Spyder/GTS until 2023, or longer?
I think the Top Gear article was tosh.
Wasn’t the 911‘s new larger PDK designed to support a mild hybrid? In theory it could fit the mid-engine platform with smaller storage than a full EV.
I think the differences between 3.0L 911 and 4.0L engines are misunderstood. They have a lot of common technologies that eliminate duplications in castings, coatings, tooling, machining and assembly processes and whilst the first version was turbo charged I don’t think there is a huge development cost to be absorbed necessitating high volumes. Of course they want mid-engined car volumes to be high, but no more than the higher margin 911. They will soon have a new technology engine family comprising a 911 turbo charged 3.0L cooking version, 4.0L na mini GT, and to be launched 992 GT na and (guess) 4.0 Turbo. All incorporate the future emission-ready technologies so my view is that it is all part of engine family development cost.
Journalists seem to concentrate on average fleet emissions constraints which seem to be a choice for OEMs to pay fines or lose money on compliance with small EV cars, but I think Euro 7 will be a bigger issue particularly with new model certifications.
Wasn’t the 911‘s new larger PDK designed to support a mild hybrid? In theory it could fit the mid-engine platform with smaller storage than a full EV.
I think the differences between 3.0L 911 and 4.0L engines are misunderstood. They have a lot of common technologies that eliminate duplications in castings, coatings, tooling, machining and assembly processes and whilst the first version was turbo charged I don’t think there is a huge development cost to be absorbed necessitating high volumes. Of course they want mid-engined car volumes to be high, but no more than the higher margin 911. They will soon have a new technology engine family comprising a 911 turbo charged 3.0L cooking version, 4.0L na mini GT, and to be launched 992 GT na and (guess) 4.0 Turbo. All incorporate the future emission-ready technologies so my view is that it is all part of engine family development cost.
Journalists seem to concentrate on average fleet emissions constraints which seem to be a choice for OEMs to pay fines or lose money on compliance with small EV cars, but I think Euro 7 will be a bigger issue particularly with new model certifications.
I'm inclined to agree with you on all counts Ralph.
The latest 8-speed PDK for the 992 does indeed incorporate space for a motor-generator, although I think it's quite a bit heavier than the 7-speeder. I'm sure that it could be installed with the F-4T and probably the (longer?) F-6 in a mid-engined configuration.
The 9A2 Evo engine is derived from the 3.0L turbo unit, so I'm sure that there are no problems manufacturing (same bore centre spacing) and building the two engines on the same line. As you say, a lot of the turbo engine features have been carried-over to the n/a engine.
Meeting Euro 7 will be a significant challenge for Porsche's turbo engines, let alone a large-capacity n/a engine, without some sort of hybridisation I would have thought.
Jeff
The latest 8-speed PDK for the 992 does indeed incorporate space for a motor-generator, although I think it's quite a bit heavier than the 7-speeder. I'm sure that it could be installed with the F-4T and probably the (longer?) F-6 in a mid-engined configuration.
The 9A2 Evo engine is derived from the 3.0L turbo unit, so I'm sure that there are no problems manufacturing (same bore centre spacing) and building the two engines on the same line. As you say, a lot of the turbo engine features have been carried-over to the n/a engine.
Meeting Euro 7 will be a significant challenge for Porsche's turbo engines, let alone a large-capacity n/a engine, without some sort of hybridisation I would have thought.
Jeff
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