Faster on track GT3 or TT?
05-22-2013, 03:22 PM
#121
Burning Brakes
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Looking at the components of the current cars that are prone to failure, it doesn't seem to be the more sophisticated electronic stuff that breaks. Coolent fittings, clutches, diffs and CLs are the simple mechanical things. Systems like PASM, DEM and now PDK and EPAS seem to be holding up.
Porsche electronics were so far good...but just look over the fence with the BMW 7 series from a few years ago..electronic problems all over the place..
05-22-2013, 03:33 PM
#122
Race Car
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Yeah. Lots of risk with the new GT3. RWS, updated PDK that will see lots of track miles, e-diff, new PASM, new steering software, revised centerlocks, and essentially a ground up new motor despite part of the same 9A1 engine family (the valvetrain + 9k rpm is of some concern).
Odds are something is going to give. I am betting the centerlocks will prove reliable, I think the RWS will as well since I don't think it's nearly as a complex systems as it is made out here (some are acting like it's the work of the devil). But the toughness of the new PDK setup and valvetrain leave me some concern. e-diff a toss up. . . bmw and fiat has been doing them for a while.
I think the combination of RWS and e diff will conspire to make the new metal very compelling b/c we'll see a car with unparalleled turn-in. I'm sucker for cars with exceptional turn in. . . it's gonna be epic.
Odds are something is going to give. I am betting the centerlocks will prove reliable, I think the RWS will as well since I don't think it's nearly as a complex systems as it is made out here (some are acting like it's the work of the devil). But the toughness of the new PDK setup and valvetrain leave me some concern. e-diff a toss up. . . bmw and fiat has been doing them for a while.
I think the combination of RWS and e diff will conspire to make the new metal very compelling b/c we'll see a car with unparalleled turn-in. I'm sucker for cars with exceptional turn in. . . it's gonna be epic.
05-22-2013, 03:55 PM
#123
I find the criticism of the RWS amusing, and at it's root I see a general fear of change and the unknown. The concerns over reliability are not compelling to me- the number of system that can fail and take a car out are innumerable, and many of them are completely new or redesigned with each generation. The PDK could fail and select two gears at once, locking the transmission. Any one of the power steering, ABS or ESP systems could have a bug, the motor could seize, etc. Solid engineering is required to prevent any of these failures, and while there is always a chance of getting something wrong Porsche engineering is generally near the best. They will have followed a long and through failure modes and effects analysis, and they will have put more engineering resources into this single component than many race and kit car manufactures can afford to spend on their entire cars. I see the chances of an issue on this particular system, despite the fact that it's new, as low.
What's amusing to me is that while I wouldn't want 99% of the crap on a modern car, I see the RWS system as one of the few things I'd consider. Stability control, power steering, ABS and sequential shifters are just some of the complicated toys on newer cars that make them faster but heavier, more complex and get between the driver and the car. RWS, however, promises to truly broaden the car's performance envelope in a way that addresses its worst vices, simultaneously improving both stability and agility without adding a nanny. That's the type of improvement that nearly impossible to get any other way.
We'll all see if reliability is an issue, but I predict that once this ceases to be the scary new thing and becomes par for the course (as ABS, water cooling, power steering, etc have before it) this will be a non-issue, and this debate will be forgotten. Or looked back on with amusement, for some of us.
What's amusing to me is that while I wouldn't want 99% of the crap on a modern car, I see the RWS system as one of the few things I'd consider. Stability control, power steering, ABS and sequential shifters are just some of the complicated toys on newer cars that make them faster but heavier, more complex and get between the driver and the car. RWS, however, promises to truly broaden the car's performance envelope in a way that addresses its worst vices, simultaneously improving both stability and agility without adding a nanny. That's the type of improvement that nearly impossible to get any other way.
We'll all see if reliability is an issue, but I predict that once this ceases to be the scary new thing and becomes par for the course (as ABS, water cooling, power steering, etc have before it) this will be a non-issue, and this debate will be forgotten. Or looked back on with amusement, for some of us.
05-22-2013, 03:59 PM
#124
Race Director
With 50 years of 911 development, much of it in racing and track testing, I fail to see how we can presume
to criticize the engineering, performance and long term reliability of a car that we have neither driven nor even seen. I would think intelligent criticism of its perceived track behavior, let alone its long term reliability, would at least await independent and comprehensive published reviews by those that have at least driven it.
to criticize the engineering, performance and long term reliability of a car that we have neither driven nor even seen. I would think intelligent criticism of its perceived track behavior, let alone its long term reliability, would at least await independent and comprehensive published reviews by those that have at least driven it.
Misinformation aside (primary function only under 30mph, worm drive) when you read through the concerns about reliability and other potential issues with RWS there are straw men all over the place, and enough "ifs", "no idea", "don't think so", "I doubt its", "most likelys", and other qualifiers to choke a horse. FCOL, this discussion started with a concern that RWS would be turning the rear wheels "sideways" if it failed at 120mph!
I have no idea if this is true, but I doubt very much there will be any problems with RWS and if as expected it is a robust system, and because it will allow fitment of 19" wheels, it will most likely prove to be one of the most significant handling improvements in the 911 since the multi-link rear suspension.
A presumptuous statement, you say? Maybe. But no more so than the hypothetical predictions of unsuitability and failure for RWS, based on incomplete informaton and speculation.
05-22-2013, 05:30 PM
#126
Rennlist Member
you honestly say you never saw a bended rear toe link? or other suspension arms bended?
do you realize what actual pressure it takes to bend that piece of solid metal? and now look at size and design of RWS assembly and where it sits. do you all really do not see what I see? it is not a rocket science, it is as simple as usual leverage - you hit wheel at a curb, it hits toe link.
assembly size is hardly bigger than couple inches wide where motor part is, so it is mostly 1 inch gear inside with tiny teeth that moves that link now.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
do you realize what actual pressure it takes to bend that piece of solid metal? and now look at size and design of RWS assembly and where it sits. do you all really do not see what I see? it is not a rocket science, it is as simple as usual leverage - you hit wheel at a curb, it hits toe link.
assembly size is hardly bigger than couple inches wide where motor part is, so it is mostly 1 inch gear inside with tiny teeth that moves that link now.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
05-22-2013, 05:38 PM
#127
Rennlist Member
I find the criticism of the RWS amusing, and at it's root I see a general fear of change and the unknown. The concerns over reliability are not compelling to me- the number of system that can fail and take a car out are innumerable, and many of them are completely new or redesigned with each generation. The PDK could fail and select two gears at once, locking the transmission. Any one of the power steering, ABS or ESP systems could have a bug, the motor could seize, etc. Solid engineering is required to prevent any of these failures, and while there is always a chance of getting something wrong Porsche engineering is generally near the best. They will have followed a long and through failure modes and effects analysis, and they will have put more engineering resources into this single component than many race and kit car manufactures can afford to spend on their entire cars. I see the chances of an issue on this particular system, despite the fact that it's new, as low.
What's amusing to me is that while I wouldn't want 99% of the crap on a modern car, I see the RWS system as one of the few things I'd consider. Stability control, power steering, ABS and sequential shifters are just some of the complicated toys on newer cars that make them faster but heavier, more complex and get between the driver and the car. RWS, however, promises to truly broaden the car's performance envelope in a way that addresses its worst vices, simultaneously improving both stability and agility without adding a nanny. That's the type of improvement that nearly impossible to get any other way.
We'll all see if reliability is an issue, but I predict that once this ceases to be the scary new thing and becomes par for the course (as ABS, water cooling, power steering, etc have before it) this will be a non-issue, and this debate will be forgotten. Or looked back on with amusement, for some of us.
What's amusing to me is that while I wouldn't want 99% of the crap on a modern car, I see the RWS system as one of the few things I'd consider. Stability control, power steering, ABS and sequential shifters are just some of the complicated toys on newer cars that make them faster but heavier, more complex and get between the driver and the car. RWS, however, promises to truly broaden the car's performance envelope in a way that addresses its worst vices, simultaneously improving both stability and agility without adding a nanny. That's the type of improvement that nearly impossible to get any other way.
We'll all see if reliability is an issue, but I predict that once this ceases to be the scary new thing and becomes par for the course (as ABS, water cooling, power steering, etc have before it) this will be a non-issue, and this debate will be forgotten. Or looked back on with amusement, for some of us.
Ive driven RWS in a Prelude I once had and more recently in a Nissan GTR. I never had any issues with 4WS reliability and a number of colleagues with 4WS in the GTR (albiet a different system) have not had reliability issues since they purchased their cars new in 2009 on road or track (which is the primary use for their GTRs).
Remember the system is on the TT/TTS as stock as well (but with a greater 2.5 degrees of articulation!). I imagine it will also filter into the entire range from generation 2 onwards.
In two separate interviews AP makes comment that now the engine can be assembled on a production line there will be far better control of quality nd that one concern of the low volume Mezger engine towards the end of its production like was the quality control of suppliers low volume parts. I know of a few 3.8RS engines and a couple of 4.0RS engines that have suffered reliability issues and I guess this may have been what AP was alluding too. The of course there is the rinky dink 3.8/4,0 CL issue so even these models we all covert so much are not free from glitches....
I have seen the technical details of the new CL system and it looks like a total revision. The distributor in NZ has a tech notes documents on the new 991 GT3 which is 100 pages long. a few have seen it but they will not give out a copy at this time. I expect the same document exists in Europe and the USA with PNA. I am trying to source a copy. It complements the 38 page sales suppliment that many have also not yet seen which goes into greater detail about the features of the car.
For the first time ever the GT3 is only 0.2-0.4 seconds slower to 62 mph than a new model TT and TTS. Top speed of the GT3 is infact 1 mph faster than the TT and 1mph slower than the TTs. That's very interesting too. Moreover observers at the Ring have already indicated the GT3 is good for 7.26 (although Porsche may publish otherwise). Unlike previous generations of GT3 I believe this one has been subjected to 2-3 x the test Kms as it was an entirely new ground up platform for a GT.
As others have said above we can only speculate until the truth is known, but I wouldnt underestimate Porsche on this model. In all their dealer sales literature I have they repeatedly make reference to track use and reliability. This was clearly a key focus of the development of this car...
05-22-2013, 05:42 PM
#128
Rennlist Member
you honestly say you never saw a bended rear toe link? or other suspension arms bended?
do you realize what actual pressure it takes to bend that piece of solid metal? and now look at size and design of RWS assembly and where it sits. do you all really do not see what I see? it is not a rocket science, it is as simple as usual leverage - you hit wheel at a curb, it hits toe link.
assembly size is hardly bigger than couple inches wide where motor part is, so it is mostly 1 inch gear inside with tiny teeth that moves that link now.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
do you realize what actual pressure it takes to bend that piece of solid metal? and now look at size and design of RWS assembly and where it sits. do you all really do not see what I see? it is not a rocket science, it is as simple as usual leverage - you hit wheel at a curb, it hits toe link.
assembly size is hardly bigger than couple inches wide where motor part is, so it is mostly 1 inch gear inside with tiny teeth that moves that link now.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
By the way Peter I believe is very well qualified to know the properties of metals/alloys!!!
05-22-2013, 06:03 PM
#129
Personally I think changes like RWS are worth the risk if they result in some measurable benefit or really do add something new to the driving experience. If you want them to test a system in racing beforehand, we'll be waiting years and the price of the feature will be uncompetitive if it's built to the same spec as a race car.
05-22-2013, 06:19 PM
#130
Rennlist Member
there is a term in mechanical engineering - a factor of safety. I am sorry but I can simply tell what it is just from looking at this thing, believe what you want or not to, may be I am a naysayer indeed, drive this thing if you want, test its limits, I will not.
05-22-2013, 06:27 PM
#131
Race Director
assembly size is hardly bigger than couple inches wide where motor part is, so it is mostly 1 inch gear inside with tiny teeth that moves that link now.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
I can only hope the body of that assembly is at least half as strong as my ERP solid steel joints and whole thing will not simply pop out of it after a decent hit at a curb.
People are getting all riled up over RWS in, at best, a partial information vacuum. You'd think they would have learned something from the weeks of wild and incorrect speculation about how the new GT3 was going to have a wet sump, slightly-warmed-over Carrera powerkit motor.
Last edited by Mike in CA; 05-22-2013 at 06:47 PM.
05-22-2013, 06:32 PM
#132
Rennlist Member
Due respect, Paul, but you're making basic assumptions that are incorrect. For example, the brushless DC motor actuator operates the threaded toe adjustment spindle via a belt drive, not via "a gear with tiny teeth". I'm smart enough to realize when I don't have the engineering details, so I can't confirm anything more, but it's possible this system is more robust than a gear driven one and allows for isolation of the actuator from forces on the toe link.
05-22-2013, 07:00 PM
#133
Nordschleife Master
I found this article interesting :
http://www.autozine.org/technical_sc...spension21.htm
Pay attention to the Weissach axle suspension introduced by Porsche in the mid 70's in the Award Winning 928! It seems to me Porsche had the rear wheel steering in mind a long long long time ago!
http://www.autozine.org/technical_sc...spension21.htm
Pay attention to the Weissach axle suspension introduced by Porsche in the mid 70's in the Award Winning 928! It seems to me Porsche had the rear wheel steering in mind a long long long time ago!
Last edited by neanicu; 08-31-2016 at 08:59 AM.
05-22-2013, 08:34 PM
#134
Rennlist Member
What if the new 20" wheel develops a structural fracture at 200 kmph?
What if the the new rockers haven't been properly tested to 9000 rpm on US tracks?
What if the new steering wheel paddles havent been attached properly to their assembly?
What if the electromagnetic active engine mount works it connection loose?
What if the steering wheel falls off in your hands on the track????
Common guys. This is getting really silly now. Its a compliment to the 991 GT3 that people are now moving on from seats, PDK and CL to RWS gubbins failure but its a bit ridiculous dont you think to start to target new tech areas we have no knowledge on isnt it? Im mean it sPorsche not nassa sending Apollo to the moon.
My prediction is that the 991 GT3 will prove to be more reliable across its intended design use than the outgoing 3.8RS GT3 (which the more I read on the 997 GT3 thread the more I realize this was probably a step down in reliability as a package from the 997.1 GT3!).
What if the the new rockers haven't been properly tested to 9000 rpm on US tracks?
What if the new steering wheel paddles havent been attached properly to their assembly?
What if the electromagnetic active engine mount works it connection loose?
What if the steering wheel falls off in your hands on the track????
Common guys. This is getting really silly now. Its a compliment to the 991 GT3 that people are now moving on from seats, PDK and CL to RWS gubbins failure but its a bit ridiculous dont you think to start to target new tech areas we have no knowledge on isnt it? Im mean it sPorsche not nassa sending Apollo to the moon.
My prediction is that the 991 GT3 will prove to be more reliable across its intended design use than the outgoing 3.8RS GT3 (which the more I read on the 997 GT3 thread the more I realize this was probably a step down in reliability as a package from the 997.1 GT3!).
05-22-2013, 10:12 PM
#135
Nordschleife Master
I found this article interesting :
http://www.autozine.org/technical_sc...spension21.htm
Pay attention to the Weissach axle suspension introduced by Porsche in the mid 70's in the Award Winning 928! It seems to me Porsche had the rear wheel steering in mind a long long long time ago!
http://www.autozine.org/technical_sc...spension21.htm
Pay attention to the Weissach axle suspension introduced by Porsche in the mid 70's in the Award Winning 928! It seems to me Porsche had the rear wheel steering in mind a long long long time ago!