997 GT3 Gen1 clubsport
Discussion
From my experience of owning and tracking a 997.1 GT3 for the last 7 years the traction control button doesn't fully turn it off. The car eats it rear brakes 5 times faster than the fronts, so I don't believe that's the ABS. Last season I change over to R29 pads this has helped with wear rates but still about 3 times quick than the fronts.
Does anyone know what the ramp angle are in the 997 diff? I believe the 996 was 40/60 how does the 7 differ, been told by others that the standard 7 ramp angle contributes to the brake wear issue. Is that possible?
Does anyone know what the ramp angle are in the 997 diff? I believe the 996 was 40/60 how does the 7 differ, been told by others that the standard 7 ramp angle contributes to the brake wear issue. Is that possible?
Cunno said:
From my experience of owning and tracking a 997.1 GT3 for the last 7 years the traction control button doesn't fully turn it off. The car eats it rear brakes 5 times faster than the fronts, so I don't believe that's the ABS. Last season I change over to R29 pads this has helped with wear rates but still about 3 times quick than the fronts.
Does anyone know what the ramp angle are in the 997 diff? I believe the 996 was 40/60 how does the 7 differ, been told by others that the standard 7 ramp angle contributes to the brake wear issue. Is that possible?
I think off is off with the TC. I left it off most of the time on my gen 1 and rear pad wear wasn't a big issue. On my Gen 2 The rear pads have lasted 3x the fronts...i think on the gen 2 its PSM that gobbles pads and TC is not intervening that much at all when its on. on the gen 1 with no PSM then when TC is on its a bit digital in its operation. But if its off its off. The rear pad wear is probably more to do with the std f/r brake bias.Does anyone know what the ramp angle are in the 997 diff? I believe the 996 was 40/60 how does the 7 differ, been told by others that the standard 7 ramp angle contributes to the brake wear issue. Is that possible?
The diff on the 997 (both .1 and .2) has ramp rates of 28/40
These cars have a component under the wider umbrella of TC (though its managed via the ABS system/sensors) that applies the rear brakes automatically to a wheel to replicate the function of a mechanical diff.
The other components of TC are slip control and engine drag control and are controlled by adjusting the acceleration input to the engine.
The ABS also controls the bias on the car. Under heavy braking it spikes the rear pressure and then removes the line pressure from the rear system all without the driver doing anything (or indeed realising). If you run line pressure sensors its quite interesting to see on the data trace of this happening.
You are therefor limited in your ability to change this behaviour. Whatever changes you make you cannot prevent this dumping of pressure from the rear system.
Learning to maximise the use of the ABS system by adjusting brake application is the cheapest way to getting the most from the braking. Swapping out the ABS unit for a race one is the best but also the most expensive.
This situation is not unique to the 997 GT3 btw. Its a modern ABS situation.
I posted a video some time back from a brake seminar held by Darrick Dong, head of motorsports at performance friction that discussed this effect and how to work with ABS on track to get the most from the brake system. I thought it might have been of interest but it was an hour long so most skipped it. For those interested you may be able to find it in a search. Its easily worth a watch/listen.
These cars have a component under the wider umbrella of TC (though its managed via the ABS system/sensors) that applies the rear brakes automatically to a wheel to replicate the function of a mechanical diff.
The other components of TC are slip control and engine drag control and are controlled by adjusting the acceleration input to the engine.
The ABS also controls the bias on the car. Under heavy braking it spikes the rear pressure and then removes the line pressure from the rear system all without the driver doing anything (or indeed realising). If you run line pressure sensors its quite interesting to see on the data trace of this happening.
You are therefor limited in your ability to change this behaviour. Whatever changes you make you cannot prevent this dumping of pressure from the rear system.
Learning to maximise the use of the ABS system by adjusting brake application is the cheapest way to getting the most from the braking. Swapping out the ABS unit for a race one is the best but also the most expensive.
This situation is not unique to the 997 GT3 btw. Its a modern ABS situation.
I posted a video some time back from a brake seminar held by Darrick Dong, head of motorsports at performance friction that discussed this effect and how to work with ABS on track to get the most from the brake system. I thought it might have been of interest but it was an hour long so most skipped it. For those interested you may be able to find it in a search. Its easily worth a watch/listen.
fioran0 said:
The diff on the 997 (both .1 and .2) has ramp rates of 28/40
These cars have a component under the wider umbrella of TC (though its managed via the ABS system/sensors) that applies the rear brakes automatically to a wheel to replicate the function of a mechanical diff.
The other components of TC are slip control and engine drag control and are controlled by adjusting the acceleration input to the engine.
The ABS also controls the bias on the car. Under heavy braking it spikes the rear pressure and then removes the line pressure from the rear system all without the driver doing anything (or indeed realising). If you run line pressure sensors its quite interesting to see on the data trace of this happening.
You are therefor limited in your ability to change this behaviour. Whatever changes you make you cannot prevent this dumping of pressure from the rear system.
Learning to maximise the use of the ABS system by adjusting brake application is the cheapest way to getting the most from the braking. Swapping out the ABS unit for a race one is the best but also the most expensive.
This situation is not unique to the 997 GT3 btw. Its a modern ABS situation.
Thanks, forgive me if this is a silly question, but if I'm reading this right what your saying is the ABS is kicking in to assist the diff and this could explain the excessive rear brake wear or is it the ABS bias spiking to the rear which is causing the rear brake pad wear? These cars have a component under the wider umbrella of TC (though its managed via the ABS system/sensors) that applies the rear brakes automatically to a wheel to replicate the function of a mechanical diff.
The other components of TC are slip control and engine drag control and are controlled by adjusting the acceleration input to the engine.
The ABS also controls the bias on the car. Under heavy braking it spikes the rear pressure and then removes the line pressure from the rear system all without the driver doing anything (or indeed realising). If you run line pressure sensors its quite interesting to see on the data trace of this happening.
You are therefor limited in your ability to change this behaviour. Whatever changes you make you cannot prevent this dumping of pressure from the rear system.
Learning to maximise the use of the ABS system by adjusting brake application is the cheapest way to getting the most from the braking. Swapping out the ABS unit for a race one is the best but also the most expensive.
This situation is not unique to the 997 GT3 btw. Its a modern ABS situation.
Would increasing the diff ramp angle to a 40/60 help?
Also I'm assume from what I have read else where that the TC Is actually off when off so this is all to do with ABS unit which can't be switched off?
The pad wear is related to the wheels being physically braked by the ABD to replicate a conventional diff. As the actual LSD in the gearbox wears out the amount of work that the ABD would have to do would increase adding to pad wear.
The system monitors for a difference in rotational speeds of the wheels via the abs sensors and reacts when certain conditions are reached.
I would imagine that a diff with more lock would require less intervention by the system when such conditions were reached and also reduce the number of times the ABD felt it had to to anything in the first place.
I also agree that TC off means off with respect to the systems that operate via engine control, but am not 100% on whether this also includes the ABD portion. I believe that ABD remains on at all times but don't know unequivocally.
The system monitors for a difference in rotational speeds of the wheels via the abs sensors and reacts when certain conditions are reached.
I would imagine that a diff with more lock would require less intervention by the system when such conditions were reached and also reduce the number of times the ABD felt it had to to anything in the first place.
I also agree that TC off means off with respect to the systems that operate via engine control, but am not 100% on whether this also includes the ABD portion. I believe that ABD remains on at all times but don't know unequivocally.
Found this earlier, but still not sure if off means off? Can't say I've ever felt it kick in though once switched off.
[QUOTE=911SLOW;8597068]Gentlemen: for the sake of accuracy please note that according to the published technical information for the 997.1 GT3 you can [U]completely turn off[/U] the electronic aids.
I have driven a 7.1 GT3 with the traction control off and never felt that it came back on, even at extreme angles ..
[I][B]
Traction Control/ABS [/B]
In “Traction Control” (TC), the 911 GT3 is provided for the first time with a system to promote driving stability during acceleration. This system comes as standard and is used in a similar manner on the Carrera GT. It incorporates the following features:
• ABD (automatic brake differential)
• ASR (anti-slip regulation) including MSR (engine drag torque control)
In conjunction with the familiar anti-lock brake system (ABS) and the Traction Control (TC) system tuned specifically for the new 911 GT3, the latter now possesses a system to promote driving stability during both braking and accelerating. TC supports straight-line stability and overall driving stability in particular in adverse weather conditions such as rain or when varying levels of grip apply on the road surface. When drive wheels begin to spin, the automatic brake differential function (ABD) first of all brakes the wheel with a higher level of slip. If both wheels are spinning, ASR will intervene within fractions of a second. The purpose of the anti-slip regulation (ASR) function is to prevent excess wheel slip on the drive wheels in order to increase cornering traction at the rear axle. The ASR function is activated when accelerating across the entire speed range. As a result of intervention in the engine control system, the engine power is decreased via a reduction in torque, acceleration and ignition angle. When ASR is activated, the relevant information light lights up on the instrument cluster. This yellow information light displays a warning triangle to indicate that the adhesion limit has been reached. Engine drag torque control (MSR) is a function within ASR. This function takes effect, for example, when there is a risk of a loss of lateral stability at the rear axle after a downshift on a slippery surface due to rear wheels locking as a result of engine drag torque. In such a situation, MSR can quickly open the throttle by demanding more power from the engine management system, thereby restoring driving stability.
SPORT / TC OFF
To enable the car’s driving dynamics to be increased according to individual needs, the standard “SPORT” button for Traction Control on the centre console enables a sporty set-up with delayed intervention by the ABD, ASR and MSR functions [U]or, alternatively, the entire system can be switched off via the “TC OFF” button. “[/U]TC OFF” appears on the instrument cluster display when the system is switched off.[/I][/QUOTE]
[QUOTE=911SLOW;8597068]Gentlemen: for the sake of accuracy please note that according to the published technical information for the 997.1 GT3 you can [U]completely turn off[/U] the electronic aids.
I have driven a 7.1 GT3 with the traction control off and never felt that it came back on, even at extreme angles ..
[I][B]
Traction Control/ABS [/B]
In “Traction Control” (TC), the 911 GT3 is provided for the first time with a system to promote driving stability during acceleration. This system comes as standard and is used in a similar manner on the Carrera GT. It incorporates the following features:
• ABD (automatic brake differential)
• ASR (anti-slip regulation) including MSR (engine drag torque control)
In conjunction with the familiar anti-lock brake system (ABS) and the Traction Control (TC) system tuned specifically for the new 911 GT3, the latter now possesses a system to promote driving stability during both braking and accelerating. TC supports straight-line stability and overall driving stability in particular in adverse weather conditions such as rain or when varying levels of grip apply on the road surface. When drive wheels begin to spin, the automatic brake differential function (ABD) first of all brakes the wheel with a higher level of slip. If both wheels are spinning, ASR will intervene within fractions of a second. The purpose of the anti-slip regulation (ASR) function is to prevent excess wheel slip on the drive wheels in order to increase cornering traction at the rear axle. The ASR function is activated when accelerating across the entire speed range. As a result of intervention in the engine control system, the engine power is decreased via a reduction in torque, acceleration and ignition angle. When ASR is activated, the relevant information light lights up on the instrument cluster. This yellow information light displays a warning triangle to indicate that the adhesion limit has been reached. Engine drag torque control (MSR) is a function within ASR. This function takes effect, for example, when there is a risk of a loss of lateral stability at the rear axle after a downshift on a slippery surface due to rear wheels locking as a result of engine drag torque. In such a situation, MSR can quickly open the throttle by demanding more power from the engine management system, thereby restoring driving stability.
SPORT / TC OFF
To enable the car’s driving dynamics to be increased according to individual needs, the standard “SPORT” button for Traction Control on the centre console enables a sporty set-up with delayed intervention by the ABD, ASR and MSR functions [U]or, alternatively, the entire system can be switched off via the “TC OFF” button. “[/U]TC OFF” appears on the instrument cluster display when the system is switched off.[/I][/QUOTE]
Gentlemen, this information is extremely useful. Mt initial thoughts are that The diff set up and function is key if a car is to be built maximise an analogue nature. The rearward brake bias under initial braking can be utilised more effectively if a particular braking technique were required and there appears to be more scope for front camber on the 97 than the 996 as the abs may not be as restricting as there is less front bias on initial braking. It looks like, getting the most out of a 997 is going to be interesting in terms of set up and driving technique when compared to a 996.
Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Steve Rance said:
Gentlemen, this information is extremely useful. Mt initial thoughts are that The diff set up and function is key if a car is to be built maximise an analogue nature. The rearward brake bias under initial braking can be utilised more effectively if a particular braking technique were required and there appears to be more scope for front camber on the 97 than the 996 as the abs may not be as restricting as there is less front bias on initial braking. It looks like, getting the most out of a 997 is going to be interesting in terms of set up and driving technique when compared to a 996.
Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Morning Steve. Couldn't sleep thinking about the new toy ? Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Neil has frequently said in the past that the 996 GT3's (and I think specifically the Mk1) were the closest to their Cup counterparts, and that as the GT3 has evolved, it's Cup counterparts have got further and further removed from the road cars.
It was always going to happen as the engineers at Stuttgart sought to tame the inherent "issues" of the rear engine layout for fast road use.
Steve Rance said:
Gentlemen, this information is extremely useful. Mt initial thoughts are that The diff set up and function is key if a car is to be built maximise an analogue nature. The rearward brake bias under initial braking can be utilised more effectively if a particular braking technique were required and there appears to be more scope for front camber on the 97 than the 996 as the abs may not be as restricting as there is less front bias on initial braking. It looks like, getting the most out of a 997 is going to be interesting in terms of set up and driving technique when compared to a 996.
Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Sir, I will be watching this thread and your updates with great interest as I want to add a set of passives to my .1 RS and to date have held off due to being totally in the dark re set-up. Not being resident in the UK means that I will be shamelessly copying whatever info you post here.Certainly its pretty obvious why the 997 cup has an adjustable brake bias system. its also obvious why there is a huge void between the driving dynamics of the 997 road car (GT3) and the Cup car. I originally thought that this was solely a PASM issue but it clearly goes a lot deeper than that. My aim is to create similar dynamics of the 997 Cup in my road GT3 and from the past few posts I think i'm feeling a bit more optimistic but it's going to be a little tricky.
Slippydiff said:
Morning Steve. Couldn't sleep thinking about the new toy ?
Neil has frequently said in the past that the 996 GT3's (and I think specifically the Mk1) were the closest to their Cup counterparts, and that as the GT3 has evolved, it's Cup counterparts have got further and further removed from the road cars.
It was always going to happen as the engineers at Stuttgart sought to tame the inherent "issues" of the rear engine layout for fast road use.
Ha. unfortunately not. lots of work to do before the christmas break. Yep, any 996 is a very close descendant. My 6RS was basically the same as the 6 Cup that I raced in terms of feel and dynamics - not close, I mean the same. After my first test in a 7 Cup, I couldn't believe how good the package was and how beautiful it was to drive. The road car was so different, the lack of feel by comparison very marked. The great thing is that it has the capacity to be a lot better…Neil has frequently said in the past that the 996 GT3's (and I think specifically the Mk1) were the closest to their Cup counterparts, and that as the GT3 has evolved, it's Cup counterparts have got further and further removed from the road cars.
It was always going to happen as the engineers at Stuttgart sought to tame the inherent "issues" of the rear engine layout for fast road use.
Hi Steve, this thread is very interesting, insightful, and for me also an affirmation of how a well sorted 996 should be setup.
From my side, my journey has taken some five 996 GT3 variants before I stumbled on the right setup sweetspot. It did not need to take five, but I was also a complete newbie the first time around and did not really go 'the whole hog' in the intervening cars.
I sense you are now recreating this sweetspot in the newer 997 platform and that is very intreaging.
I appreciate this thread is about 997s...but just to share what I loved about the 996, and if you can recreate that in a 997 it would be awesome!
So for me the sweetspot on the 996 has been:
1. Uprated suspension.
Stiffer springs with a secondary assister to smooth road use
(Front: 80N main / 40N helper; Rear: 140N main / 60N helper)
In my car I have Nitron adjustable dampers (though perhaps any other decent brand could be equally good)
I have started to understand which tracks need some adjustment to account for different levels of bumpiness. But overall the degrees of adjustment needed are relatively minor.
2. Strong/fresh diff
Motorsport plates correctly shimmed.
3. Good geo
In order to work with the diff...I do not have the numbers at hand but something like 3 deg of negative camber, lowered front, good rake
4. Sharper brakes
I use GiroDiscs all round with RS29 pads. Beautiful initial bite, ongoing feel, and consistency.
They also happen to have braided hoses but not sure if this adds/detracts from anything
The general front biased brakes mean you can really feel what is happening at the front of the car with respect to weight transfer and adhesion limits during straight line and trail braking. The diff keeps the rear under control as well.
...and that's it.
(well, apart from BBS slightly wider alloys, 5mm spacers, and Cup 2 tyres )
But i find this setup so bloody amazing. The confidence it inspires has meant my lap times have tumbled this year (ok, my starting base was probably a bit low )
...but now I am using the throttle pedal to control the car as much as the brake and steering wheel.
So much so, that recently having the option of this 996 GT3 and a 4.0 on a slightly slippery track with one session to go, I opted for the 996 GT3 for that last bit of all out fun.
And although it is no comfort barge, with the dual springs road driving is not compromised either.
All the above may sound like what's wrong with the standard unmodified car - and the answer is nothing at all. All the above changes are (in my mind) tweaks to the base platform. Optimising it for greater involvement and personal learning. That's what makes the GT3 line so excellent for drivers who want to go on a journey. Everyone has a different end point and different path.
In my case I also have to credit Nine Excellence who helped me with the fine tuning of the car...I am sure there are other good sources of advice as well.
So, a bit of an aside on a 996, but as I read your objectives I feel I also get excited at the prospect of potentially creating a similar feel in the newer 997 platform
...I might have to join you
Good luck with your journey.
From my side, my journey has taken some five 996 GT3 variants before I stumbled on the right setup sweetspot. It did not need to take five, but I was also a complete newbie the first time around and did not really go 'the whole hog' in the intervening cars.
I sense you are now recreating this sweetspot in the newer 997 platform and that is very intreaging.
I appreciate this thread is about 997s...but just to share what I loved about the 996, and if you can recreate that in a 997 it would be awesome!
So for me the sweetspot on the 996 has been:
1. Uprated suspension.
Stiffer springs with a secondary assister to smooth road use
(Front: 80N main / 40N helper; Rear: 140N main / 60N helper)
In my car I have Nitron adjustable dampers (though perhaps any other decent brand could be equally good)
I have started to understand which tracks need some adjustment to account for different levels of bumpiness. But overall the degrees of adjustment needed are relatively minor.
2. Strong/fresh diff
Motorsport plates correctly shimmed.
3. Good geo
In order to work with the diff...I do not have the numbers at hand but something like 3 deg of negative camber, lowered front, good rake
4. Sharper brakes
I use GiroDiscs all round with RS29 pads. Beautiful initial bite, ongoing feel, and consistency.
They also happen to have braided hoses but not sure if this adds/detracts from anything
The general front biased brakes mean you can really feel what is happening at the front of the car with respect to weight transfer and adhesion limits during straight line and trail braking. The diff keeps the rear under control as well.
...and that's it.
(well, apart from BBS slightly wider alloys, 5mm spacers, and Cup 2 tyres
)But i find this setup so bloody amazing. The confidence it inspires has meant my lap times have tumbled this year (ok, my starting base was probably a bit low
)...but now I am using the throttle pedal to control the car as much as the brake and steering wheel.
So much so, that recently having the option of this 996 GT3 and a 4.0 on a slightly slippery track with one session to go, I opted for the 996 GT3 for that last bit of all out fun.
And although it is no comfort barge, with the dual springs road driving is not compromised either.
All the above may sound like what's wrong with the standard unmodified car - and the answer is nothing at all. All the above changes are (in my mind) tweaks to the base platform. Optimising it for greater involvement and personal learning. That's what makes the GT3 line so excellent for drivers who want to go on a journey. Everyone has a different end point and different path.
In my case I also have to credit Nine Excellence who helped me with the fine tuning of the car...I am sure there are other good sources of advice as well.
So, a bit of an aside on a 996, but as I read your objectives I feel I also get excited at the prospect of potentially creating a similar feel in the newer 997 platform
...I might have to join you
Good luck with your journey.
Edited by LaSource on Wednesday 17th December 11:16
Sounds like you've had a fun journey getting to where you want to be. That's the joy of the 996, the elements are already there, With the 997, more work will be needed but I think in the end, the main difference will be getting the bias right. I really do not want to have to drive around a moving bias and would much prefer a mechanical diff to stabilise the rear of the car under braking. In the 997 cup,/ on the track you want the bias as far to the front as possible unless conditions are slippery.
The one thing that I don't think that we will be able to replicate is the level of engagement through the chassis that the 996 has. It's chassis isn't as stiff as the 997 but it's not too soft as to ruin the spring damping platform. Just enough to give that extra little bit of 'aliveness' - call it what you will - that makes it such a delight to drive. The 977 will be slightly more clinical /efficient and slightly less engaging in this area because of it. The upside is that ihas more potential and may well more engaging in different ways.
The one thing that I don't think that we will be able to replicate is the level of engagement through the chassis that the 996 has. It's chassis isn't as stiff as the 997 but it's not too soft as to ruin the spring damping platform. Just enough to give that extra little bit of 'aliveness' - call it what you will - that makes it such a delight to drive. The 977 will be slightly more clinical /efficient and slightly less engaging in this area because of it. The upside is that ihas more potential and may well more engaging in different ways.
Steve Rance said:
We found a way of running pretty high degrees of front camber without needing a motorsport ABS unit on the 996 so we have the same aim on the 997.
Would you mind sharing the details of the 996 setup?LaSource said:
1. Uprated suspension.
Stiffer springs with a secondary assister to smooth road use
(Front: 80N main / 40N helper; Rear: 140N main / 60N helper)
In my car I have Nitron adjustable dampers (though perhaps any other decent brand could be equally good)
Interesting, these are the same rates the Ohlins DFV kit runs for the 996 GT3, although they don't seem to use helpers.Stiffer springs with a secondary assister to smooth road use
(Front: 80N main / 40N helper; Rear: 140N main / 60N helper)
In my car I have Nitron adjustable dampers (though perhaps any other decent brand could be equally good)
Cunno said:
Posted an extract from the tech info for the 997.1 TC from the Porsche literature
TBH, I tend to take the position that assuming the opposite of whatever the marketing mentions is probably accurate on all things.I still smile at the same article waxing lyrical about the new longer rods for the 997.1
It was a bosch thing I had read where it sounded like the ABD wasn't switchable but I can't find it to look back on. It may very well all cut off on the 997.1 It would be better for pad life if it did thats for sure.
One thing I always wondered about the use of brakes to do the job of the diff was how it performs under hard braking where the 911 really needs the diff to lock up. I wonder if it can do the role of braking while adjusting each side to work as a locked diff at the same time.
Steve,
Im interested to hear where you are aiming with this a little more. Its been interesting reading your posts of late and hearing your views from behind the wheel.
I know we are on the same page with regards the car and how much the platform has to offer (having had the pleasure of the 997 cups) when it comes to the road car.
Theres some interesting things introducing with the 997 Cup that moves it away from the street cars and the 996 cup from the driving perspective though and your comments ref the 996 prompted me to ask.
These aspects raise some interesting questions if one is wanting to take a 997 GT3 further in this direction that just opening up the car and involve some hard decisions. Its not that they are difficult technically to achieve but that they require an approach that would very much be beyond that which was needed to remove the layer of insulation and reveal the platform for what it can be.
The 996 Cup can very much be driven in the same basic way one drives all the street cars (including the most fettled track modded ones) i.e. you drive on the front end with a ton of steering feel and control.
The 997 cup is absolutely not driven in this way and trying to do it leaves you ploughing wide.
Instead you drive it from the rear end, with pretty much zero steering feel and learn to trust it. I always found the big braking was done hard and fast using the massive brake force the car can pull in the initial phase.
This whole aspect was probably the single biggest hump to get over when I moved up to 997 tbh. It wasn't like any approach id used before.
The other obvious difference with the 997 Cup is that its not a car that you drive holding the wheel between the fingertips of your thumb and forefinger, pinkies aloft as you massage the pedals with some italian loafers. Its a car that responds to being treated like a mean ba$tard. Its a physical drive and treating the road car like this, even with race dampers etc would leave it crying.
Ignoring the intensity, the noise and the concentration levels needed in any 996 or 997 Cup, these two aspects above are strong features of the 997 cup from the drivers seat imho.
And this gets back round to my original point. Are you coming with the objective that you want to let the qualities of the 997 platform out or are you wanting to take it a level beyond that to try and replicate these aspects of the 997 cup in your car too. I see the potential in both approaches btw, I was just interested to hear where you are at in your head.
I appreciate that its still a conceptual process and these things often resolve organically once one starts - when do you get the car btw? - so feel free to ignore.
Im interested to hear where you are aiming with this a little more. Its been interesting reading your posts of late and hearing your views from behind the wheel.
I know we are on the same page with regards the car and how much the platform has to offer (having had the pleasure of the 997 cups) when it comes to the road car.
Theres some interesting things introducing with the 997 Cup that moves it away from the street cars and the 996 cup from the driving perspective though and your comments ref the 996 prompted me to ask.
These aspects raise some interesting questions if one is wanting to take a 997 GT3 further in this direction that just opening up the car and involve some hard decisions. Its not that they are difficult technically to achieve but that they require an approach that would very much be beyond that which was needed to remove the layer of insulation and reveal the platform for what it can be.
The 996 Cup can very much be driven in the same basic way one drives all the street cars (including the most fettled track modded ones) i.e. you drive on the front end with a ton of steering feel and control.
The 997 cup is absolutely not driven in this way and trying to do it leaves you ploughing wide.
Instead you drive it from the rear end, with pretty much zero steering feel and learn to trust it. I always found the big braking was done hard and fast using the massive brake force the car can pull in the initial phase.
This whole aspect was probably the single biggest hump to get over when I moved up to 997 tbh. It wasn't like any approach id used before.
The other obvious difference with the 997 Cup is that its not a car that you drive holding the wheel between the fingertips of your thumb and forefinger, pinkies aloft as you massage the pedals with some italian loafers. Its a car that responds to being treated like a mean ba$tard. Its a physical drive and treating the road car like this, even with race dampers etc would leave it crying.
Ignoring the intensity, the noise and the concentration levels needed in any 996 or 997 Cup, these two aspects above are strong features of the 997 cup from the drivers seat imho.
And this gets back round to my original point. Are you coming with the objective that you want to let the qualities of the 997 platform out or are you wanting to take it a level beyond that to try and replicate these aspects of the 997 cup in your car too. I see the potential in both approaches btw, I was just interested to hear where you are at in your head.
I appreciate that its still a conceptual process and these things often resolve organically once one starts - when do you get the car btw? - so feel free to ignore.
Congrats on the car Steve
I'm sure you will come to enjoy it in time when you start sorting the small stuff.
I have not taken the greatest of steps in modifying mine - but some have been well chosen.
I have mine kept at the Nürburgring, and seen after by Tom Schirmer (Who most of you will probably know for his BMW work)
Currently I'm running endlass pads on the OEM discs by Toms recommendation. Can't tell you much about Wear on them, as I'm still on my first set (which has done more than 100 laps of the Ring this year)
It was fitted with a HR 997 cup racing suspension setup when I bought it - courtesy of the previous owner from Sweden and his racing team running in the Swedish Carrera Cup with another 997 Cup car. This setup was not road legal in Germany and was changed for a full Nitron adjustable coilover suspension with external reservoirs for the front dampers. The car was subsequently corner weighted and a full Geo was done for the Ring (and then raised by about 5 mm as the car was scraping quite a lot on the Ring
)
I'm sure the rear antiroll bar has been changed also, as I have never had any mentionable problems with understeer.
My thoughts on the next upgrades have been centered around weight saving by an Akrapovic exhaust and a light weight battery.
Looking forward to reading your Progress on the car and sharing experiences.
Mine is a keeper - and I wouldnt even change it for a 4.0 for fear of ruining my economy.
CK
I'm sure you will come to enjoy it in time when you start sorting the small stuff.
I have not taken the greatest of steps in modifying mine - but some have been well chosen.
I have mine kept at the Nürburgring, and seen after by Tom Schirmer (Who most of you will probably know for his BMW work)
Currently I'm running endlass pads on the OEM discs by Toms recommendation. Can't tell you much about Wear on them, as I'm still on my first set (which has done more than 100 laps of the Ring this year)
It was fitted with a HR 997 cup racing suspension setup when I bought it - courtesy of the previous owner from Sweden and his racing team running in the Swedish Carrera Cup with another 997 Cup car. This setup was not road legal in Germany and was changed for a full Nitron adjustable coilover suspension with external reservoirs for the front dampers. The car was subsequently corner weighted and a full Geo was done for the Ring (and then raised by about 5 mm as the car was scraping quite a lot on the Ring
) I'm sure the rear antiroll bar has been changed also, as I have never had any mentionable problems with understeer.
My thoughts on the next upgrades have been centered around weight saving by an Akrapovic exhaust and a light weight battery.
Looking forward to reading your Progress on the car and sharing experiences.
Mine is a keeper - and I wouldnt even change it for a 4.0 for fear of ruining my economy.
CK
fioran0 said:
Steve,
Im interested to hear where you are aiming with this a little more. Its been interesting reading your posts of late and hearing your views from behind the wheel.
I know we are on the same page with regards the car and how much the platform has to offer (having had the pleasure of the 997 cups) when it comes to the road car.
Theres some interesting things introducing with the 997 Cup that moves it away from the street cars and the 996 cup from the driving perspective though and your comments ref the 996 prompted me to ask.
These aspects raise some interesting questions if one is wanting to take a 997 GT3 further in this direction that just opening up the car and involve some hard decisions. Its not that they are difficult technically to achieve but that they require an approach that would very much be beyond that which was needed to remove the layer of insulation and reveal the platform for what it can be.
The 996 Cup can very much be driven in the same basic way one drives all the street cars (including the most fettled track modded ones) i.e. you drive on the front end with a ton of steering feel and control.
The 997 cup is absolutely not driven in this way and trying to do it leaves you ploughing wide.
Instead you drive it from the rear end, with pretty much zero steering feel and learn to trust it. I always found the big braking was done hard and fast using the massive brake force the car can pull in the initial phase.
This whole aspect was probably the single biggest hump to get over when I moved up to 997 tbh. It wasn't like any approach id used before.
The other obvious difference with the 997 Cup is that its not a car that you drive holding the wheel between the fingertips of your thumb and forefinger, pinkies aloft as you massage the pedals with some italian loafers. Its a car that responds to being treated like a mean ba$tard. Its a physical drive and treating the road car like this, even with race dampers etc would leave it crying.
Ignoring the intensity, the noise and the concentration levels needed in any 996 or 997 Cup, these two aspects above are strong features of the 997 cup from the drivers seat imho.
And this gets back round to my original point. Are you coming with the objective that you want to let the qualities of the 997 platform out or are you wanting to take it a level beyond that to try and replicate these aspects of the 997 cup in your car too. I see the potential in both approaches btw, I was just interested to hear where you are at in your head.
I appreciate that its still a conceptual process and these things often resolve organically once one starts - when do you get the car btw? - so feel free to ignore.
Hi NeilIm interested to hear where you are aiming with this a little more. Its been interesting reading your posts of late and hearing your views from behind the wheel.
I know we are on the same page with regards the car and how much the platform has to offer (having had the pleasure of the 997 cups) when it comes to the road car.
Theres some interesting things introducing with the 997 Cup that moves it away from the street cars and the 996 cup from the driving perspective though and your comments ref the 996 prompted me to ask.
These aspects raise some interesting questions if one is wanting to take a 997 GT3 further in this direction that just opening up the car and involve some hard decisions. Its not that they are difficult technically to achieve but that they require an approach that would very much be beyond that which was needed to remove the layer of insulation and reveal the platform for what it can be.
The 996 Cup can very much be driven in the same basic way one drives all the street cars (including the most fettled track modded ones) i.e. you drive on the front end with a ton of steering feel and control.
The 997 cup is absolutely not driven in this way and trying to do it leaves you ploughing wide.
Instead you drive it from the rear end, with pretty much zero steering feel and learn to trust it. I always found the big braking was done hard and fast using the massive brake force the car can pull in the initial phase.
This whole aspect was probably the single biggest hump to get over when I moved up to 997 tbh. It wasn't like any approach id used before.
The other obvious difference with the 997 Cup is that its not a car that you drive holding the wheel between the fingertips of your thumb and forefinger, pinkies aloft as you massage the pedals with some italian loafers. Its a car that responds to being treated like a mean ba$tard. Its a physical drive and treating the road car like this, even with race dampers etc would leave it crying.
Ignoring the intensity, the noise and the concentration levels needed in any 996 or 997 Cup, these two aspects above are strong features of the 997 cup from the drivers seat imho.
And this gets back round to my original point. Are you coming with the objective that you want to let the qualities of the 997 platform out or are you wanting to take it a level beyond that to try and replicate these aspects of the 997 cup in your car too. I see the potential in both approaches btw, I was just interested to hear where you are at in your head.
I appreciate that its still a conceptual process and these things often resolve organically once one starts - when do you get the car btw? - so feel free to ignore.
Apologies for the delay. I wanted to give you a considered reply.
To be honest, I'm not entirely sure. As you say, the 996 Cup has a more delicate feel through the steering and brakes compared to the 97 Cup. Actually I found the electric steering on the 997 pretty good and the weight saving was useful. The feel is not as good as the 996 but it's ok. It was the brakes that are horribly wooden compared to the 996. As you say, this encourages a much more 'leap of faith' driving style, although in time it is possible to dial yourself into the car and drive on 100% feel and adopt the same style as a 996 - but it isn't as easy. I know a lot of very good drivers that struggled to get to terms with the 997. Oddly, for different reasons it's the brakes on the road car that are giving me the biggest headache at this stage. The moving bias/ABD is a real problem to me. For my needs, the diff function needs to be completely separate from the braking system. I must be able to rely on the diff being consistant and push the brake bias a lot more forward. As you say, currently under the initial braking phase, there is no surplus capacity for the rear brakes to do anything else and In slow corners, Ill be taking almost 100% brake on turn in so, again hardly any capacity for them to help the diff - so where does that leave the effectiveness of the diff in the current set up during the phase that I most need it? Whats worse is that it's mechanical function is made of chocolate. I've had several moments in 997Gt3's on the track where the car has gone into oversteer without any prior warning just after turn in. Until now, i'd put this down to me applying too much brake trying to drive around understeer caused by the dreaded PASM. I now believe that these were possibly caused by rear braking of the loaded wheel by the ABD system and not by the PASM. This is interesting because if i'm right, in it's standard form the car actually has the worst of both worlds because of it's active systems. PASM encouraging understeer during certain phases and ABD encouraging oversteer in certain phases. I think that because some drivers do not ask the car to operate in the performance zone where these issues may occur, its a non problem. For the driver who does achieve these performance levels, it can be a real problem.
For me, both 'active' systems (PASM and ABD - lets call it the brake assisted diff) have to go in order to create a stable platform. It's essential to have 100% confidence in a car's predictability at 1-11/10ths. To 'get rid' of the ABD, I'm hoping that a motorsport diff pack with 40:60 ramping will work. I am aware that I'm relying on preventing the circumstances for the ABD sensors being triggered here. The part of this process that worries me is whether the ABS sensor has the ABD function as part of its programming or whether it's a separate control unit. If its a separate unit, the next issue is to get the brake bias further forward. If it's part of the ABS function, i may have a lot more problems. The good news here is that the peddle feel should be much better than the 997 cup so hopefully once the bias issue is resolved, braking will have a lovely feel. With the braking, i'll start 'greedy' and try to add more braking capacity to the front rather than removing it from the rear but that all comes down to balancing braking capability with the grip factor of the front tyres as I won't want front camber compromised. This was the only real problem that we had with the 996. We couldn't run the front camber that we wanted to because the contact patch was too small under braking and the ABS kept kicking in. We can't fit a 997 motorsport unit because it didn't have one and I don't want to fit the 996 unit because it would make the car a bit of a hybrid which in an ideal world i don't want.
Once the Diff and braking issues are sorted, the damping and geo will be a doodle. The final touch will be a cup steering wheel. It makes a noticeable difference to steering feel to ditch the extra weight of the airbag etc.. (providing you can live with the extra kick back which I rather enjoy).
We were absolutely spoiled with the 996. We just changed the damping, spent a lot of time and effort perfecting different geos from blunt to super sharp, threw on some beefed up front discs, a set of yellows and a cup steering wheel. Hey presto! you had a stunning car that pretty much dynamically mirrored the cup. With the 997 it will be different because as you say, the 997 Cup has unique differences to the road car, mainly electric steering and no abs just an adjustable bias. In some ways these systems are not net losses to the road car. The Electric steering does give a chunky weight saving gain and the feel isn't too far behind the normal rack but I think for the level of tuning that i'm looking for, I'll take the normal rack and a little more feel. The brakes are a real double edged sword. On the one hand, the road car forgoes the infinite bias adjustability of the race car but on the other hand it has a lot more pedal feel that the race system and - being a road car - really should retain it's abs system. The problem is that the bias is wrong and undoing/correcting it may be a problem. If we are lucky, the road car may end up with nicer steering and a better brake feel than the race car. Finally, the race car has a proper diff and damping which the road car certainly does not. These are both losses that the road car really does miss.
So to answer your question - what am i looking for from the car. I think it will not be possible to mirror the Cup experience because some elements of the cup car cannot realistically be relocated on the road car. But in some ways that will not be a loss to the driving experience because the braking and steering feel of the Cup car are not porsche's finest hour in terms of driving enjoyment - which is what this project is all about. Ideally, I wanted to do what we did to the 996. Bolt on some springs and dampers, stronger front brakes, geo etc. and unlock a stunning road track tool with the minimum of fettling. With the 997 it is no going to be as easy but the philosophy is the same. To unlock as much of the true dynamic potential of the car as possible with the minimum of modifications. I think that this journey is going to be difficult to plot but I am hopeful that we may create something very special.
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