GT4 RS breaks cover then...

[Escy]

I expect an oil cooler would solve these issues

[Twinfan]

TDT said:

The 7-speed PDK used in the GT4 RS is enhanced significantly:

- 1st to 7th gear and constant axle ratio from 991.2 GT3 RS PDK
- Bevel gear with GT4RS-specific design made of high-grade motorsport material
- Limited slip differential from the 991.2 GT3 MT locking values (30% traction / 37% overrun)
- Pressurised oiling of the main shaft bearings via an external oiling line
- Dual mass flywheel from the 982 GT4 Clubsport
- Hydraulic ventilation system analogous to 982 GT4 Clubsport
- PDK control unit and software from 991.2 GT3RS with GT4RS specific application
- Gearshift lever design analogous to 992 GT3
- Gearshift lever actuation from 991.2 GT3RS
- GT4RS-specific selector cable with higher temperature-resistant end piece material

Thanks T, I knew you'd know and have access to the technical "stuff" It's very clear in the cars that the PDK in the GT4RS is quite different to that in the non-RS.

TDT said:

Was out in a 4RS today @ Zandvoort. Honestly… as much fun as I had in my manual GT4…. I don’t know that I’d miss manual change very much at all with the 4RS engine and PDK. It’s so sharp, and just gives you more options.
That said, the satisfaction of being ‘quick’ whilst managing all of the workload in a manual is something to savour, and really sticks with you.

While not as quick as you, the bolded part is what floats my boat.

Escy said:

The gearbox is impressive from a technological standpoint but not rewarding as a driving tool and surely that's what it's all about? I guess the rest of the package makes up for it.

I wouldn't change the manual gearbox in my car to shave a second off the 1/4 mile time or a couple off a lap time. Getting the gear changes bang on adds to the adrenaline.

also the way I feel. I'm not racing so I'm not bothered if I'm 2 mins or 2 mins 10 secs around Oulton Park

With all that said though, the GT4RS is an immense piece of kit for those who are able to buy one and even more so if they can do it justice with their driving!

[ChrisW.]

Escy said:

I expect an oil cooler would solve these issues

Might this be part of the hydraulic ventilation system ?

RPM Technik have (so far as I am aware) not opted for an oil cooler ...

P.S. Thanks for the info T

[johnycarrera]

Thanks T, I knew you'd know and have access to the technical "stuff" It's very clear in the cars that the PDK in the GT4RS is quite different to that in the non-RS.

[quote=TDT]


Seems like I’m arguing but I’m genuinely not, what from any of that made it very clear that the PDK is quite different?
I’m reading that it has a different control module, for its different engine, but nothing about the shift speed parameters or characteristics or design of the PDK system. I’d much rather people either said I don’t know or I don’t have the words to explain it but back to back the gearbox feels very different…. I’m well aware it’s a different engine and revs higher, the ratios are shorter etc (9K is spine tingling when you’re stuck with a lowly 8)

I guess perceptions are different for each of us and it’s only a forum…..

[Twinfan]

johnycarrera said:

Seems like I’m arguing but I’m genuinely not, what from any of that made it very clear that the PDK is quite different?
I’m reading that it has a different control module, for its different engine, but nothing about the shift speed parameters or characteristics or design of the PDK system. I’d much rather people either said I don’t know or I don’t have the words to explain it but back to back the gearbox feels very different…. I’m well aware it’s a different engine and revs higher, the ratios are shorter etc (9K is spine tingling when you’re stuck with a lowly 8)

I guess perceptions are different for each of us and it’s only a forum…..

Without being a Porsche employee specifially involved in the development of the car I'm not sure what you're expecting me to say, but this is the key part I think:

"PDK control unit and software from 991.2 GT3RS with GT4RS specific application"

You do seem very insistent that they're the same despite a couple of us saying they're different based on experience and T posting all the technical specs - why so?

[TDT]

Escy said:

I expect an oil cooler would solve these issues

GT4 gearboxes are equipped with oil cooler as standard.

Edited by TDT on Wednesday 24th May 11:23

[TDT]

Twinfan said:

johnycarrera said:

Seems like I’m arguing but I’m genuinely not, what from any of that made it very clear that the PDK is quite different?
I’m reading that it has a different control module, for its different engine, but nothing about the shift speed parameters or characteristics or design of the PDK system. I’d much rather people either said I don’t know or I don’t have the words to explain it but back to back the gearbox feels very different…. I’m well aware it’s a different engine and revs higher, the ratios are shorter etc (9K is spine tingling when you’re stuck with a lowly 8)

I guess perceptions are different for each of us and it’s only a forum…..

Without being a Porsche employee specifially involved in the development of the car I'm not sure what you're expecting me to say, but this is the key part I think:

"PDK control unit and software from 991.2 GT3RS with GT4RS specific application"

You do seem very insistent that they're the same despite a couple of us saying they're different based on experience and T posting all the technical specs - why so?

Many manufacturers used to publish ever improving shift times and other numerical data, when these new gen of dual clutch/DCT/DSG/PDK gearboxes…. Porsche did that initially… 991.1 GT3 and .1 RS… but then really have stopped quoting numbers as they have reached a level where it doesn’t really matter… and/or increasingly marginal improvements are harder and more expensive to achieve.

So main differences now come from:

- Shift strategy… in 4RS, more aggressive… that is to say it is more keenness to change gears up or down as per the input conditions.
- Shorter ratios…
- additional ‘strengthening’ for more sustained high loading use case…. same box is used on the 4RS Clubsport race car.

[johnycarrera]

Twinfan said:

Without being a Porsche employee specifially involved in the development of the car I'm not sure what you're expecting me to say, but this is the key part I think:

"PDK control unit and software from 991.2 GT3RS with GT4RS specific application"

You do seem very insistent that they're the same despite a couple of us saying they're different based on experience and T posting all the technical specs - why so?

I just want to know is all, I guess it’s just semantics without tech specs of both including numeracy, where’s a modern day Pope when you need him!

I’m over it, you guys don’t know but say you do, I really only want to know about shift speeds which I can’t find anywhere….. I’ll go away for another few years again leave you guys to it.

[Twinfan]

I don't think the info you want is necessarily out there, and for me personally I'm not looking at just the speed of the shift in isolation. I'm also not looking for an argument I was just passing on my experience having been in both cars with the same driver for the sake of discussion

[Escy]

TDT said:

Escy said:

I expect an oil cooler would solve these issues

GT4 gearboxes are equipped with oil cooler as standard.

I was thinking an aftermarket oil cooler that uses air flow to cool it. The efficency of those heat exchangers are limited by the coolant temperature.

[TDT]

johnycarrera said:

, I really only want to know about shift speeds which I can’t find anywhere…..

I answered this is exact question.
Porsche don’t publish anymore… they don’t seem to think it matters these days with advancements in the tech…the numbers used to be proof-point during early development.

I guess you must be thinking if there are not hardware differences and it’s just software… can I update mine to match?
Some ECU tuners used to do shift strategy mapping… e.g Cobb…but they have moved away from that due to wanting to remain relevant in a tightening emissions compliance environment.

[200Plus Club]

Escy said:

I was thinking an aftermarket oil cooler that uses air flow to cool it. The efficency of those heat exchangers are limited by the coolant temperature.

Water is used for 2 purposes, warms it up quicker from cold plus gets rid of excessive heat once upto temp. I believe its actually preferred to use water cooling for these applications

[Escy]

For a road car it is.

[TDT]

[mep59]

johnycarrera said:

What significant (but not huge) behaviour exactly?
Genuinely interested as to me it feels the same as the non RS GT3s I’ve driven with regards to shift speed and seamless-ness/ lack of inertia thump of the changes (I’ve not driven the 3RS or 4RS)

I don't know much about the technical details - but to me the difference is most noticeable at slower speeds, where the gearbox will change gears more abruptly than the GT4 version.

Also, the GT3RS I would never drive in auto mode, even on the road - the GT4 (both engine and gearbox) is much more civilised when you're not on it.

I guess the gearbox just feels a bit harsher to me.

[ChrisW.]

The question of shift speed also has the counter argument of mechanical sympathy.

I recall my CR PDK having three settings ... I never used the fastest change because it felt harsher than I felt was necessary.

I drove always in the middle setting which felt racy enough and kind enough

[200Plus Club]

Watching the GT4RS video with Henry Catchpole that was the first time I'd realised you can use the "gear nob" as a sequential shifter on a pdk rather than the paddles if you wish. Looked like the perfect road car for those perfect roads.

[TDT]

Has been the case with PDK since 991 GT3 onwards and then into 718… that they corrected the actuation of the shift.

Prior to 991 GT3, PDK shifter was forwards for UP and backwards for DOWN.

Thereafter it has been corrected to forwards for DOWN and backwards for UP.

[TDT]

Seems like there is some cooling in the market for these now…

OPC has one up for 214k and have heard of off market movements for used cars at 200k.
Still crazy money, of course, but might mean that with supply increasing via more deliveries and also Spyder RS… we might get start to see lightly used 4RS at more sensible prices.

[Twinfan]

I thought it looked weird using like that, I'd just use the paddles