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Re: 997 Turbo overbuust question
Quote:
arakis said:
hi I was wondering is the function, time limited like u can use it once every 5 min, like for overtacking on a highway? Actualy anyone who knows how it works and what are the limitations is welcome.
I really hope the overboost can be used more than every 5 minutes because, as you wisely pointed out, how can else could you overtake on the highway???
Surely not with only 480 hp and 620 Nm, I mean, that's pathetic!
Re: 997 Turbo overbuust question
Quote:
arakis said:
hi I was wondering is the function, time limited like u can use it once every 5 min, like for overtacking on a highway? Actualy anyone who knows how it works and what are the limitations is welcome.
As far as I know, there are no limitations. Yes, it is an option to allow excessive boost for around 10 seconds to allow faster passing/overtaking as soon as you FULLY apply the throttle. As soon as you release the throttle, you can use the overboost function again but again only for 10 seconds. This is NOT a limitation, it is a feature. And as far as I heard, it comes ONLY with the sport chrono package Turbo.
Re: 997 Turbo overbuust question
Actually, after having thought about it, Arakis's point is not without reason.
Here's a toy, a gizmo, whatever, that'll only be engaged for 10 secs.
RC,
When did you use the boost feature on you Lancia, I mean, for what means?
For fast starts? Overtaking? (That's something the Turbo won't need surely, unless, you're up against another Turbo without sports chrono package on the motorway).
Is this the sort of feature that one can use on the track or on a twisty road for example?
Would the driver have to activate the feature at the exit of each turn to increase torque availibility keeping in mind there must be more than 10 seconds between turns before he can use it again.
Is 680 Nm too high for the engine to take for this torque figure to be permanent?
Every Turbo driver will be like David Hasslehof is his Kit car with the mighty red overboost button!
Here's a toy, a gizmo, whatever, that'll only be engaged for 10 secs.
RC,
When did you use the boost feature on you Lancia, I mean, for what means?
For fast starts? Overtaking? (That's something the Turbo won't need surely, unless, you're up against another Turbo without sports chrono package on the motorway
).Is this the sort of feature that one can use on the track or on a twisty road for example?
Would the driver have to activate the feature at the exit of each turn to increase torque availibility keeping in mind there must be more than 10 seconds between turns before he can use it again.
Is 680 Nm too high for the engine to take for this torque figure to be permanent?
Every Turbo driver will be like David Hasslehof is his Kit car with the mighty red overboost button!
Re: 997 Turbo overbuust question
Fanch, I guess it's best thinking on what happens on a racetrack. Unless you are on an oval, there will almost never be a situation where you stay on full throttle for more than 10 secs. Even on the straights in Monza I dont think 10 secs are reached. but nonetheless one would use the overboost all the time (in the sense that it would kick in very often) after the partializing of throttle ends at the exit of a bend. which makes sense cause you dont want to have the extra boost kick in in the middle of a bend. 
This will be a heck of a feature, combined with PDK - which unfortunately is not yet available - it will be a seamless thrust out of the chicanes as if there was no tomorrow!!!
This will be a heck of a feature, combined with PDK - which unfortunately is not yet available - it will be a seamless thrust out of the chicanes as if there was no tomorrow!!!
1 févr. 2006 12:29:57
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Carlos from Spain
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- En réponse de: arakis
Re: 997 Turbo overbuust question
Quote:
arakis said:
stupid me, sorry. yea probably the gt2 version will have 700Nm+ all the time
Have you ever driven a 996 GT2 on the track? Trust me, you have to be an excellent driver to be able to keep up with those GT3 MkII because the high torque and turbo boost actually create a lot of problems for unexperienced drivers.
So unless somebody is Walter Röhrl, I suggest sticking with GT2 stock power or better...get a tuned 911 Turbo and you'll blow away most of the cars around the track even with less developped driver skills.
Re: 997 Turbo overbuust question
Now we have what appear to be authorised power/torque numbers for the 997tt of 480PS/620NM one can speculate further on the overboost function. According to the reports it will give 680NM for "short bursts".
For a motor which in 996tt form could give over 700NM reliably with just an exhaust and ECU modification this new engine with its further advancements, (especially the variable vane turbos which should allow much greater efficiency and colder intake air which is THE most important feature, keeping the engine away from its knock limits)would easily be able to run 680NM ALL the time, no problem - I'm afraid this feature is Porsche giving its customers a spanking $$$$$$
IF I get one of these I would forego this feature and wait for the tuners to crack the ECU - 680NM will be a joke compared to what is waiting in there.
For a motor which in 996tt form could give over 700NM reliably with just an exhaust and ECU modification this new engine with its further advancements, (especially the variable vane turbos which should allow much greater efficiency and colder intake air which is THE most important feature, keeping the engine away from its knock limits)would easily be able to run 680NM ALL the time, no problem - I'm afraid this feature is Porsche giving its customers a spanking $$$$$$
IF I get one of these I would forego this feature and wait for the tuners to crack the ECU - 680NM will be a joke compared to what is waiting in there.
Re: 997 Turbo overbuust question
Quote:
TB993tt said:
IF I get one of these I would forego this feature and wait for the tuners to crack the ECU - 680NM will be a joke compared to what is waiting in there.
I have to repeat myself again: it is the whole package which counts. I've driven lots of tuned Porsche and I can assure you that most of them weren't very well tuned. They were all very powerful but driving on a twisty little country road with more than 1.0 bar boost pressure all the time, even at third throttle position, isn't any fun at all. Just an example. So unless we're talking drag racing here, more torque and more power are pretty much useless in achieving better track times as long as the power/torque figures don't come in values you really need in certain driving conditions.
I suggest driving a tuned 996 GT2 with around 600 HP and a 1.3 bar boost pressure. After two rounds in Hockenheim, I left this car and told the owner that it is undriveable. And this guy was wondering why he couldn't "beat" those tuned 996 Turbos out there.
But please get me right: I'm pretty sure that sooner or later, I'll add some horses to my 997 Turbo, no doubt about it. But IF I do it, I try to do it the right way, meaning: from Porsche (powerkit) or, if not possible, from a reputable Porsche tuner who already has a year or two experience with VTG engine tuning. And if I have to pay more for that, no problem. But I'm pretty sure that 6 months after the 997 Turbo shows up, there will be already ECU upgrades available, promising 50 horses and more out of nothing through a simple ECU mod only. From my personal experience with such mods, I'd say: stay away from them. They're cheap and you get exactly what you're paying for. Sometimes the programmers of such software don't even bother to adapt the mapping, they just tweak the boost pressure and maybe fuel output and thats it.
For short red light races or a few full throttle runs on some deserted country roads, no problem. But driving at top speed for a few minutes and/or doing some really hard track racing with such cars will surely make sure that the engine and maybe parts of the drivetrain too will soon move into Nirvana.
Have you looked up the price tag of a 996 Turbo engine lately? Little hint: the 997 Turbo engine will be slightly more expensive. And kiss your warranty good-bye because the undetectable ECU mod is...a MYTH.
1 févr. 2006 18:44:45
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Carlos from Spain
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En réponse de:
Futch
Re: 997 Turbo overbuust question
Quote:
Fanch said:Quote:
arakis said:
yeah for inexpirienced drvers, for those that know what they are doing more power is always a good thing.
Not that I would qualify myself as an experienced driver, but given the choice, I'd rather have less weight than more power.
I wouldn't qualify myself as one either, but I know what they (very experienced drivers) would say the exact same thing.
Also there is the small detail, and that that "power" is too gerenal a term, and power delivery plays a very important factor that, many who get caught up in absolute numbers at max revs, tend to forget.
You can have all the power in the world but you will only be able to use the one that you can apply to the ground coming out of a corner...
1 févr. 2006 18:59:42
- LB
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En réponse de:
Carlos from Spain
Re: 997 Turbo overbuust question
A bit off topic but I assume this overboost function should be similar to the ones used in A1 cars,
One of the main reasons why i prefer A1 over F1. The drivers get to use the overboost function three times during the race and when they do so (you can tell because their driver pic starts to flash red on telly) they just beast the through the other cars due to their increased hp.
One of the main reasons why i prefer A1 over F1. The drivers get to use the overboost function three times during the race and when they do so (you can tell because their driver pic starts to flash red on telly) they just beast the through the other cars due to their increased hp.
Re: 997 Turbo overbuust question
Would this 10 sec limit mean that the Variable Geometry turbos start to overheat quickly in the overboost mode, or is it just a marketing tip to impress customers?? 
I guess that both torque AND power increase with this function, by briefly increasing the turbo pressure.That would give between 5 and 10 extra bhp, am i wrong?
What do tech specialists think about it?Are VTG less reliable than others, would it be more difficult to tune these kind of engines??
I guess that both torque AND power increase with this function, by briefly increasing the turbo pressure.That would give between 5 and 10 extra bhp, am i wrong?
What do tech specialists think about it?Are VTG less reliable than others, would it be more difficult to tune these kind of engines??
2 févr. 2006 01:03:42
- Jim_in_Iowa
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En réponse de:
RC
Re: 997 Turbo overbuust question
Quote:
RC said:Quote:
arakis said:
stupid me, sorry. yea probably the gt2 version will have 700Nm+ all the time
Have you ever driven a 996 GT2 on the track? Trust me, you have to be an excellent driver to be able to keep up with those GT3 MkII because the high torque and turbo boost actually create a lot of problems for unexperienced drivers.
So unless somebody is Walter Röhrl, I suggest sticking with GT2 stock power or better...get a tuned 911 Turbo and you'll blow away most of the cars around the track even with less developped driver skills.
Here's a GT2 vs GT3 story. In 2003, the employees from PCNA in Atlanta came over to Barber Motorsports in Birmingham, where PDE is held, for the company picnic. One of the big features was hot laps from the PDE instructors for employees and families. The instructors gobbled up all the GT3s, and left head instructor Hurley Heywood with the lone GT2. Hurley would come in, a bit fatigued from wrestling with the GT2, and would try and talk one of the other instructors into trading. They all told him no, that's okay, you keep the fastest car, we'll stick with these slower GT3s. Of course the GT3s are much easier to drive, so doing lap after lap wasn't as hard on them as Hurley. That's the story I heard, anyway.
Jim
Re: 997 Turbo overbuust question
Quote:
TB993tt said:
Now we have what appear to be authorised power/torque numbers for the 997tt of 480PS/620NM one can speculate further on the overboost function. According to the reports it will give 680NM for "short bursts".
For a motor which in 996tt form could give over 700NM reliably with just an exhaust and ECU modification this new engine with its further advancements, (especially the variable vane turbos which should allow much greater efficiency and colder intake air which is THE most important feature, keeping the engine away from its knock limits)would easily be able to run 680NM ALL the time, no problem - I'm afraid this feature is Porsche giving its customers a spanking $$$$$$
IF I get one of these I would forego this feature and wait for the tuners to crack the ECU - 680NM will be a joke compared to what is waiting in there.
TB993tt,
I have sympathy for what you are arguing, after all, the stock 996TTS peak torque is 457lb-ft or 620Nm-the same as rumoured on the 997baseTT (sans overboost). HOWEVER, and this is where RC's point is important about power and torque across the rev-range and with varying outputs graded to throttle pressure, what we call driveability , peak power and torque numbers alone don't do justice to the car's performance: With the VTG's spooling quickly, 620Nm (with 680 with OB) at low rev's, can produce superior performance in a 997TT versus a 996TT with KKK16 or 24 turbo's, due to BOTH decreased T-lag and OB. AND with the 997TT's improved chassis (not to mention possible lighter weight yielding higher power-to-weight and torque-to-weight ratios at a given rpm), the car's available power will more efficiently translate to higher speeds in the turns. So peak HP and torque numbers on a 996TT don't directly correlate with peak HP and torque numbers on a 997TT. All this means that, while YES, peak power and torque numbers DO matter, this is only the "tip of the iceberg" when measuring performance, if you will pardon the expression, all the more reason to WAIT until the official specs. AND independent reviews/testdrives (likely to be reported first HERE on rennteam) come in. And this recommendation comes from a 996TTS owner on my dealer's waiting list for a 997TT who advocates modding the 996TT-HINT: Look below at my signature summarizing the 911Turbo I own.
I also think the 997TT will be easily modded with ECU upgrade and minor mechanical mods to handle the added thermal stress, but I too will prefer the Porsche powerkit (or the "S") over an aftermarket tuning-not just for warranty protection, but also because the factory upgrade will be based on extensive testing for reliability through trial and error, two reasons the aftermarket for 997TT upgrades will be riskier, especially in the first couple years after launch.
BTW, I am betting the overboost feature (in the Sports Chrono Turbo package) will be automatically actuated in the Bosch-Motronic program-based on right foot-controlled throttle manipulation, rather than fired from a switch on the dash or steering wheel, as I suspect some people think-I could be wrong, but I think a more sophisticated system would be hooked up to the throttle-simply keep the Sports Chrono Turbo mode in the "On" postiiton, floor it and feel the whiplash!
Re: 997 Turbo overbuust question
Al, Think of all of the complexity Porsche neds just to make near 500hp. Its really silly when you see non turbo'd high reving engines with 500 plus hp, Ferrari for example.
Im not implying that the 997TT motor isnt good, blah blah, but really, Porsche seems hell bent on staying with the most complex way to make power with the highest service costs when they could do better with a new engine.
The whole idea of a turbocharged 6 is so yesterday.
They need a motor rethink. I think its time for a 5 liter flat 8.
Im not implying that the 997TT motor isnt good, blah blah, but really, Porsche seems hell bent on staying with the most complex way to make power with the highest service costs when they could do better with a new engine.
The whole idea of a turbocharged 6 is so yesterday.
They need a motor rethink. I think its time for a 5 liter flat 8.
Re: 997 Turbo overbuust question
Quote:
Turbo Al said:Quote:
[
TB993tt,
I have sympathy for what you are arguing, after all, the stock 996TTS peak torque is 457lb-ft or 620Nm-the same as rumoured on the 997baseTT (sans overboost). HOWEVER, and this is where RC's point is important about power and torque across the rev-range and with varying outputs graded to throttle pressure, what we call driveability , peak power and torque numbers alone don't do justice to the car's performance: With the VTG's spooling quickly, 620Nm (with 680 with OB) at low rev's, can produce superior performance in a 997TT versus a 996TT with KKK16 or 24 turbo's, due to BOTH decreased T-lag and OB. AND with the 997TT's improved chassis (not to mention possible lighter weight yielding higher power-to-weight and torque-to-weight ratios at a given rpm), the car's available power will more efficiently translate to higher speeds in the turns. So peak HP and torque numbers on a 996TT don't directly correlate with peak HP and torque numbers on a 997TT. All this means that, while YES, peak power and torque numbers DO matter, this is only the "tip of the iceberg" when measuring performance, if you will pardon the expression, all the more reason to WAIT until the official specs. AND independent reviews/testdrives (likely to be reported first HERE on rennteam) come in. And this recommendation comes from a 996TTS owner on my dealer's waiting list for a 997TT who advocates modding the 996TT-HINT: Look below at my signature summarizing the 911Turbo I own.
I also think the 997TT will be easily modded with ECU upgrade and minor mechanical mods to handle the added thermal stress, but I too will prefer the Porsche powerkit (or the "S") over an aftermarket tuning-not just for warranty protection, but also because the factory upgrade will be based on extensive testing for reliability through trial and error, two reasons the aftermarket for 997TT upgrades will be riskier, especially in the first couple years after launch.
BTW, I am betting the overboost feature (in the Sports Chrono Turbo package) will be automatically actuated in the Bosch-Motronic program-based on right foot-controlled throttle manipulation, rather than fired from a switch on the dash or steering wheel, as I suspect some people think-I could be wrong, but I think a more sophisticated system would be hooked up to the throttle-simply keep the Sports Chrono Turbo mode in the "On" postiiton, floor it and feel the whiplash!
I agree with everything you say here. My one reservation is with Porsche making the overboost feature an $$$ option - I guess one can see why as the "poseurs" can save their money.
I agree entirely about the "peak power" argument, these variable turbos are going to be amazing.
What I am going to find fascinating over the next couple of years in watching the tuners try and "crack" the electronics and unleash another dimension with tuned VVTs. There will only be a few who manage it - but Porsche always leave so much on the table, witness a stock 996tt versus a "chipped" one +100NM - A properly tuned 997tt is going to be something else.
Re: 997 Turbo overbuust question
Quote:
TB993tt said:Quote:
Turbo Al said:Quote:
[
TB993tt,
I have sympathy for what you are arguing, after all, the stock 996TTS peak torque is 457lb-ft or 620Nm-the same as rumoured on the 997baseTT (sans overboost). HOWEVER, and this is where RC's point is important about power and torque across the rev-range and with varying outputs graded to throttle pressure, what we call driveability , peak power and torque numbers alone don't do justice to the car's performance: With the VTG's spooling quickly, 620Nm (with 680 with OB) at low rev's, can produce superior performance in a 997TT versus a 996TT with KKK16 or 24 turbo's, due to BOTH decreased T-lag and OB. AND with the 997TT's improved chassis (not to mention possible lighter weight yielding higher power-to-weight and torque-to-weight ratios at a given rpm), the car's available power will more efficiently translate to higher speeds in the turns. So peak HP and torque numbers on a 996TT don't directly correlate with peak HP and torque numbers on a 997TT. All this means that, while YES, peak power and torque numbers DO matter, this is only the "tip of the iceberg" when measuring performance, if you will pardon the expression, all the more reason to WAIT until the official specs. AND independent reviews/testdrives (likely to be reported first HERE on rennteam) come in. And this recommendation comes from a 996TTS owner on my dealer's waiting list for a 997TT who advocates modding the 996TT-HINT: Look below at my signature summarizing the 911Turbo I own.
I also think the 997TT will be easily modded with ECU upgrade and minor mechanical mods to handle the added thermal stress, but I too will prefer the Porsche powerkit (or the "S") over an aftermarket tuning-not just for warranty protection, but also because the factory upgrade will be based on extensive testing for reliability through trial and error, two reasons the aftermarket for 997TT upgrades will be riskier, especially in the first couple years after launch.
BTW, I am betting the overboost feature (in the Sports Chrono Turbo package) will be automatically actuated in the Bosch-Motronic program-based on right foot-controlled throttle manipulation, rather than fired from a switch on the dash or steering wheel, as I suspect some people think-I could be wrong, but I think a more sophisticated system would be hooked up to the throttle-simply keep the Sports Chrono Turbo mode in the "On" postiiton, floor it and feel the whiplash!
I agree with everything you say here. My one reservation is with Porsche making the overboost feature an $$$ option - I guess one can see why as the "poseurs" can save their money.
I agree entirely about the "peak power" argument, these variable turbos are going to be amazing.
What I am going to find fascinating over the next couple of years in watching the tuners try and "crack" the electronics and unleash another dimension with tuned VVTs. There will only be a few who manage it - but Porsche always leave so much on the table, witness a stock 996tt versus a "chipped" one +100NM - A properly tuned 997tt is going to be something else.
Yes,
Are you on a dealer list for a 997TT like the rest of us?
Re: 997 Turbo overbuust question
Quote:
TB993tt said:
Hi Al
Yes I'm on the list, but probably won't be taking it. I like my Porsches raw and I feel the turbo has moved in a different direction - the 997GT2 however remains an interesting possible proposition.
I'm hoping this is mis-information, but CAR mag. said (see thread here on rennteam) that there would be no 997GT2, only the 997TT and 997TTS.
Re: 997 Turbo overbuust question
Quote:
RC said:Quote:
JimFlat6 said:
The whole idea of a turbocharged 6 is so yesterday.
They need a motor rethink. I think its time for a 5 liter flat 8.
The flat 6 is good for up to 800 HP and more. So where's the problem???
People don't seem to realise there will NEVER be a flat 8 rear engined Porsche. It's been said over and over again and by multiple sources (Web, press and mostly Wolfgang Durheimer).
It's dynamically not possible anyway.
Re: 997 Turbo overbuust question
Quote:
Fanch said:Quote:
RC said:Quote:
JimFlat6 said:
The whole idea of a turbocharged 6 is so yesterday.
They need a motor rethink. I think its time for a 5 liter flat 8.
The flat 6 is good for up to 800 HP and more. So where's the problem???
People don't seem to realise there will NEVER be a flat 8 rear engined Porsche. It's been said over and over again and by multiple sources (Web, press and mostly Wolfgang Durheimer).
It's dynamically not possible anyway.
Fanch - I realize that it might be more of challenge with respect to packaging and weight limitations, but why is it impossible? I thought with new materials and careful design that a Flat-8 could be built without increasing weight or size very much...
Do you think a mid-engined Flat-8 could return to the Porsche lineup (it's been a long time)?
Re: 997 Turbo overbuust question
Quote:
Grant said:
Fanch - I realize that it might be more of challenge with respect to packaging and weight limitations, but why is it impossible? I thought with new materials and careful design that a Flat-8 could be built without increasing weight or size very much...
Do you think a mid-engined Flat-8 could return to the Porsche lineup (it's been a long time)?
It's not so much the weight limitations but the weight distribution that would be greatly compromised.
Nothing is impossible of course, although there would have to be a serious overhang for the rear.
I have basically heard and read from official as much as non official sources that Porsche is not even considering the possibility.
As for a mid engined V8 Porsche, yes the Panamera will be, front mid engined that is.
A rear mid engined V8 model? Don't see it happening in the mid term outlook no.
Maybe who knows? But the sports car segment of Porsche is pretty well filled right now, from the Boxster to the Carrera GT!
The question is not if they could build a V8 rear engined sports car but why.
Re: 997 Turbo overbuust question
Quote:
RC said:Quote:
JimFlat6 said:
The whole idea of a turbocharged 6 is so yesterday.
They need a motor rethink. I think its time for a 5 liter flat 8.
The flat 6 is good for up to 800 HP and more. So where's the problem???
Yes,
So how about a 997TT variant with factory specs. of 800 peak HP?
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