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Aug 10, 2005 3:05:54 PM
- STRADALE
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- Loc: NY , United States
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Reply to:
Carlos from Spain
Re: C4 & C2 Image Comparison
Everything you're saying is what I've believed myself. I just trusted what I've read recently from Porsche etc. to be more accurate then my beliefs. I don't doubt what you're saying about the 997 4's performance quotes being for publicity. Anythings possible.
Hmmmmmmm. Regarding what I've read about the rear track width giving it an edge - I was thinking the 996 Carrera 4 was slower then the 996 2 because it didn't have wider tires/was heavier. What about the 996 4S (WITH WIDER TIRES)? Wasn't it also slower then the 996 2's around the track ?
Or is it not a fair comparison because it had the Turbo brakes ?
Hmmmmmmm. Regarding what I've read about the rear track width giving it an edge - I was thinking the 996 Carrera 4 was slower then the 996 2 because it didn't have wider tires/was heavier. What about the 996 4S (WITH WIDER TIRES)? Wasn't it also slower then the 996 2's around the track ?
Or is it not a fair comparison because it had the Turbo brakes ?
Aug 11, 2005 10:45:45 PM
- STRADALE
- Rennteam VIP
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- Loc: NY , United States
- Posts: 11075, Gallery
- Registered on: Mar 9, 2005
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Reply to:
Carlos from Spain
Re: C4 & C2 Image Comparison
Just got my Excellence magazine in the mail.
This is interesting.
EXCELLENCE Magazine:
While traction is enhanced, the wider rear end and rubber eats into straight-line performance against the stopwatch. The AWD 997 Carrera 4 is slower against the clock: 0-62 mph takes 5.1 seconds in the manual, or 0.1 longer than a similar, two-wheel-drive Carrera. Porsche says the 997 Carrera 4S can match the Carrera S's 4.8-second time, however. Top speeds are slightly down, at 174 mph for a C4 as opposed to 177 mph for a C2 and 179 mph for a C4S instead of 182 mph.
On a long track like the Nürburgring's Nordschliefe, however, the new Carrera 4s give up nothing to their less expensive, rear-wheel-drive cousins. Thanks to careful chassis recalibrations, Carrera S and Carrera 4S models equipped with the PASM option set in Sport mode record identical 8-minute, 2-second lap times. Wahl explains that the differences in the C4 chassis tuning targeted sharper turn-in and improved steering feel, two things we experienced while charging the hairpins on local mountain roads.
"Apart from those different wheel offsets and wider tires, the rear suspension is exactly the same as the Carrera 2/2S," explains Wahl. "That means the Carrera 2 and 4 have spring rates of 43 Neuton Meters while the C2S and C4S have stiffer 56 Nm springs." The uprated front spring rates in the C2S and C4S are also identical, at 33 Nm, but the Carrera 4 gets slightly stiffer front springs, at 30 Nm compared to the C2's 27 Nm. This is partially offset by the C2's larger, 23.6-mm diameter front anti-roll bar, however. The new C4's bar is a 22.5-mm unit.
Just how much fine-tuning Porsche has done with the anti-roll bars is evident from the plethora of permutations across the four 997 coupe models alone. All 997 Carrera models use hollow front anti-roll bars, but the Carrera 4 and 4S use front bars smaller in both overall diameter and metal gauge to reduce understeer. This means 22.5x3.5 mm in the 325-bhp, 3.6-liter Carrera 4 where the Carrera 2's bar measures 23.6x3.5 mm. For the 355-bhp, 3.8-liter Carrera 4S, the front anti-roll bar is a 23.6x3.5-mm unit compared to the RWD 997 Carrera S's 24.0x3.8-mm anti-roll bar. And, yes, the Carrera 4S bar is taken right from the base Carrera 2. The plain Carrera 4's bar is new. So the all-wheel-drive Carrera 4 and 4S use weaker front anti-roll bars to reduce understeer. Keep in mind that the extra 110 pounds imposed by the AWD system - mostly positioned at the car's sharp end - also has the effect of softening up the front end, which in itself helps to reduce understeer and improve turn-in.
http://www.excellence-mag.com/art1/art1p2.html
This is interesting.
EXCELLENCE Magazine:
While traction is enhanced, the wider rear end and rubber eats into straight-line performance against the stopwatch. The AWD 997 Carrera 4 is slower against the clock: 0-62 mph takes 5.1 seconds in the manual, or 0.1 longer than a similar, two-wheel-drive Carrera. Porsche says the 997 Carrera 4S can match the Carrera S's 4.8-second time, however. Top speeds are slightly down, at 174 mph for a C4 as opposed to 177 mph for a C2 and 179 mph for a C4S instead of 182 mph.
On a long track like the Nürburgring's Nordschliefe, however, the new Carrera 4s give up nothing to their less expensive, rear-wheel-drive cousins. Thanks to careful chassis recalibrations, Carrera S and Carrera 4S models equipped with the PASM option set in Sport mode record identical 8-minute, 2-second lap times. Wahl explains that the differences in the C4 chassis tuning targeted sharper turn-in and improved steering feel, two things we experienced while charging the hairpins on local mountain roads.
"Apart from those different wheel offsets and wider tires, the rear suspension is exactly the same as the Carrera 2/2S," explains Wahl. "That means the Carrera 2 and 4 have spring rates of 43 Neuton Meters while the C2S and C4S have stiffer 56 Nm springs." The uprated front spring rates in the C2S and C4S are also identical, at 33 Nm, but the Carrera 4 gets slightly stiffer front springs, at 30 Nm compared to the C2's 27 Nm. This is partially offset by the C2's larger, 23.6-mm diameter front anti-roll bar, however. The new C4's bar is a 22.5-mm unit.
Just how much fine-tuning Porsche has done with the anti-roll bars is evident from the plethora of permutations across the four 997 coupe models alone. All 997 Carrera models use hollow front anti-roll bars, but the Carrera 4 and 4S use front bars smaller in both overall diameter and metal gauge to reduce understeer. This means 22.5x3.5 mm in the 325-bhp, 3.6-liter Carrera 4 where the Carrera 2's bar measures 23.6x3.5 mm. For the 355-bhp, 3.8-liter Carrera 4S, the front anti-roll bar is a 23.6x3.5-mm unit compared to the RWD 997 Carrera S's 24.0x3.8-mm anti-roll bar. And, yes, the Carrera 4S bar is taken right from the base Carrera 2. The plain Carrera 4's bar is new. So the all-wheel-drive Carrera 4 and 4S use weaker front anti-roll bars to reduce understeer. Keep in mind that the extra 110 pounds imposed by the AWD system - mostly positioned at the car's sharp end - also has the effect of softening up the front end, which in itself helps to reduce understeer and improve turn-in.
http://www.excellence-mag.com/art1/art1p2.html
Re: C4 & C2 Image Comparison
Have you guys noticed this shift they're talking about ? I definately have. The first time it happened I thought the tires broke loose but I wasn't near the limit. There's an off-ramp on my way home that it happens on everytime.
When we first drove the 997 in Summer of 2004, we noticed one minor handling woe in two PASM-equipped test cars. Turning into sweeping bends, the seat of our pants gave both Editor Stout and I the feeling that the tires were gripping well but that the body was moving laterally on its rear bushings. It didn't threaten to do anything untoward, but it was the kind of subtle, unsettling glitch that shakes your confidence a bit. This small but undesirable characteristic showed up on most 993s, which introduced a rear subframe to the 911. Subsequent time with 997s - both in the U.S. and Europe - has confirmed our initial concern. Worse yet, several friends of the magazine with 996s, GT2s, and GT3s have noticed it in 997s, too.
It's an interesting quandary, because the 997 uses the same basic rear suspension design as the 996 - a series of 911s that didn't exhibit this trait. And neither does a steel-suspended 997 Carrera without PASM. No reputable scientist would dream of putting forward a theory without all the facts on the table. And, as we hadn't yet driven a 997 with Sport suspension, we wanted to do this before taking the argument a step further.
Speaking of PASM, Sport suspension, and the 997 Carrera S, we need to clear the air on another issue that's become well and truly mangled. Porsche says its 3.8-liter Carrera S with Sport suspension is capable of a 7-minute, 59-second lap of the Nürburgring with Walter Röhrl at the wheel. The base 3.6-liter 997 Carrera will turn an 8-minute, 15-second lap. When Porsche announced its Cayman S could do an 8-minute, 11-second lap, many publications - either not having read the press release fully or choosing to ignore the facts - shouted from the rooftops that the Cayman S is faster than the 997.
The press release went on to say that the Carrera was a totally basic, 3.6-liter model with standard suspension and steel brakes. The Cayman S had every possible advantage, thanks to optional PASM suspension and PCCB brakes. In the same way, we're not about to draw any final conclusions about 997 suspension without doing a back-to-back comparison of every permutation.
The day before, we had a fast run up and down some familiar roads in a red PASM-equipped C4S. Knowing what we were looking for, we soon established that whatever adjustments or changes Porsche has made to the 997 C4S have not changed the perceived lateral slack in the rear-end. It still shifts slightly mid-corner. It's a subtle thing, but it's there.
We would find one more piece of the puzzle thanks to Porsche's promise to provide us with a Sport suspension-equipped C4S test car in Monaco. During an in-depth conversation with chassis guru Georg Wahl after dinner, we gleaned some useful leads. He was intrigued by our criticism, to the point that he told us he would drive PASM and Sport suspension-equipped 997s back-to-back himself and let us know his own findings. Keen to get to the bottom of our question, he asked what speed we felt this effect - and whether we thought it was the weight of the engine moving on its own support bushings or a jacking effect rather than a pure lateral shift of the car on its suspension bushings.
To the first question, we replied that it can be felt at normal/fast road speeds, far from the limit. And, as there is no change from the 996 in engine mounts, it could not be that. After driving the Sport suspension-equipped C4S, however, a third line of thinking becomes obvious. It's the first time we've driven a 997 with the factory Sport suspension. Sitting lower and with conventional gas dampers in place of the electronic PASM units, the ride is a touch on the firm side - closer to a 2004 GT3's. That will suit the hardcore enthusiasts and track-day addicts this option is aimed at just fine, but, oddly, we feel the Sport suspension is actually less stiff at the rear end and offers a better balance between ride and handling than PASM-equipped 997s in Sport mode!
Interestingly, it also exhibits almost no trace of the lateral movement at the rear of the PASM-equipped 997. By a logical elimination of factors, we must conclude - for now, at least - that the perceived effect is an unintended by-product of the PASM system. It would be interesting to watch PASM and Sport suspension 997s go through a given corner at the same speed. Having watched Active Body Control-equipped Mercedes SL55 AMGs circulate Hockenheim at the Tuner Grand Prix, we've noticed that they try to self-level when exiting corners under power, causing some curious - to watch, from the outside - jacking effects.
When we first drove the 997 in Summer of 2004, we noticed one minor handling woe in two PASM-equipped test cars. Turning into sweeping bends, the seat of our pants gave both Editor Stout and I the feeling that the tires were gripping well but that the body was moving laterally on its rear bushings. It didn't threaten to do anything untoward, but it was the kind of subtle, unsettling glitch that shakes your confidence a bit. This small but undesirable characteristic showed up on most 993s, which introduced a rear subframe to the 911. Subsequent time with 997s - both in the U.S. and Europe - has confirmed our initial concern. Worse yet, several friends of the magazine with 996s, GT2s, and GT3s have noticed it in 997s, too.
It's an interesting quandary, because the 997 uses the same basic rear suspension design as the 996 - a series of 911s that didn't exhibit this trait. And neither does a steel-suspended 997 Carrera without PASM. No reputable scientist would dream of putting forward a theory without all the facts on the table. And, as we hadn't yet driven a 997 with Sport suspension, we wanted to do this before taking the argument a step further.
Speaking of PASM, Sport suspension, and the 997 Carrera S, we need to clear the air on another issue that's become well and truly mangled. Porsche says its 3.8-liter Carrera S with Sport suspension is capable of a 7-minute, 59-second lap of the Nürburgring with Walter Röhrl at the wheel. The base 3.6-liter 997 Carrera will turn an 8-minute, 15-second lap. When Porsche announced its Cayman S could do an 8-minute, 11-second lap, many publications - either not having read the press release fully or choosing to ignore the facts - shouted from the rooftops that the Cayman S is faster than the 997.
The press release went on to say that the Carrera was a totally basic, 3.6-liter model with standard suspension and steel brakes. The Cayman S had every possible advantage, thanks to optional PASM suspension and PCCB brakes. In the same way, we're not about to draw any final conclusions about 997 suspension without doing a back-to-back comparison of every permutation.
The day before, we had a fast run up and down some familiar roads in a red PASM-equipped C4S. Knowing what we were looking for, we soon established that whatever adjustments or changes Porsche has made to the 997 C4S have not changed the perceived lateral slack in the rear-end. It still shifts slightly mid-corner. It's a subtle thing, but it's there.
We would find one more piece of the puzzle thanks to Porsche's promise to provide us with a Sport suspension-equipped C4S test car in Monaco. During an in-depth conversation with chassis guru Georg Wahl after dinner, we gleaned some useful leads. He was intrigued by our criticism, to the point that he told us he would drive PASM and Sport suspension-equipped 997s back-to-back himself and let us know his own findings. Keen to get to the bottom of our question, he asked what speed we felt this effect - and whether we thought it was the weight of the engine moving on its own support bushings or a jacking effect rather than a pure lateral shift of the car on its suspension bushings.
To the first question, we replied that it can be felt at normal/fast road speeds, far from the limit. And, as there is no change from the 996 in engine mounts, it could not be that. After driving the Sport suspension-equipped C4S, however, a third line of thinking becomes obvious. It's the first time we've driven a 997 with the factory Sport suspension. Sitting lower and with conventional gas dampers in place of the electronic PASM units, the ride is a touch on the firm side - closer to a 2004 GT3's. That will suit the hardcore enthusiasts and track-day addicts this option is aimed at just fine, but, oddly, we feel the Sport suspension is actually less stiff at the rear end and offers a better balance between ride and handling than PASM-equipped 997s in Sport mode!
Interestingly, it also exhibits almost no trace of the lateral movement at the rear of the PASM-equipped 997. By a logical elimination of factors, we must conclude - for now, at least - that the perceived effect is an unintended by-product of the PASM system. It would be interesting to watch PASM and Sport suspension 997s go through a given corner at the same speed. Having watched Active Body Control-equipped Mercedes SL55 AMGs circulate Hockenheim at the Tuner Grand Prix, we've noticed that they try to self-level when exiting corners under power, causing some curious - to watch, from the outside - jacking effects.
Re: C4 & C2 Image Comparison
My big question is how close to the handling of the C2S does the C4S get, in terms of steering feel and in terms of understeer? I disliked my 996C4S because it just felt very nose heavy and seemed really hard to balance through a corner and steering feel always felt slightly numb. I am by my own admission not Walter Rohl or anywhere close to his skill level, but the 997C2S seems head and shoulders above the 996C4S in terms of handling and steering feel.
Does the article say that Porsche have preserved the steering feel and handling balance of the C2S or is it closer to the 996C4S? It wasn't clear to me. They talk about the engineering changes but not their impressions of whether those changes work or not.
Any more info?
Does the article say that Porsche have preserved the steering feel and handling balance of the C2S or is it closer to the 996C4S? It wasn't clear to me. They talk about the engineering changes but not their impressions of whether those changes work or not.
Any more info?
Re: C4 & C2 Image Comparison
This discussion is making my head spin. I was all set to get the C2S (ordered, and set to arrive in a week or two), but my dealership has a newly-arrived C4S sitting in their showroom optioned nearly identically to the way I'd optioned my car (with a price difference of about $6k or so). Decisions, decisions!
Re: C4 & C2 Image Comparison
I just test drove the 06 C4S coupe this afternoon and compared it to my 997S...I went from an 04 996 C4S to the 997S so I was interested in seeing the differences. In person, the wider rear was nice but subtle and I really had to look to notice it. I went on a short, 20 minute test drive, respecting the break-in so I can't comment fully on performance. It was noticeably less "peppy" than my C2S; even with the sport on and considering I have 6k miles and this was new, it just didn't have the spunk that mine does. The steering was a little heavier, difinitely noticeable but not as much as the 996 C4S. I didn't get to race around any corners so I can't comment on oversteer. It felt very confident, a little smoother and more luxurious or GT than the RWD only; would inspire more confidence in inclement weather but I enjoyed the drive back more in my 997S. I would pay extra for the wider body on a C2S, like the late model 993 C2S's and I really wish they had an X51 to test drive.
Re: C4 & C2 Image Comparison
Quote:
kkeating said:
I just test drove the 06 C4S coupe this afternoon and compared it to my 997S...I went from an 04 996 C4S to the 997S so I was interested in seeing the differences. In person, the wider rear was nice but subtle and I really had to look to notice it. I went on a short, 20 minute test drive, respecting the break-in so I can't comment fully on performance. It was noticeably less "peppy" than my C2S; even with the sport on and considering I have 6k miles and this was new, it just didn't have the spunk that mine does. The steering was a little heavier, difinitely noticeable but not as much as the 996 C4S. I didn't get to race around any corners so I can't comment on oversteer. It felt very confident, a little smoother and more luxurious or GT than the RWD only; would inspire more confidence in inclement weather but I enjoyed the drive back more in my 997S. I would pay extra for the wider body on a C2S, like the late model 993 C2S's and I really wish they had an X51 to test drive.
This was exactly the difference I felt between driving the 997 C2S and the 996 C4 (with which I spent a significant amount of time back in the day). This is why I decided I liked the C2S better, but was curious as to whether the new C4S had "fixed" the steering heaviness and overall "GT" feel.
Re: C4 & C2 Image Comparison
Here is a link to my test drive of the 997 C4S
It does feel more GT than the C2S... but the understeer is not comparable to the 996 C4S , more like 996 C4, maybe even a little bit less...
www.rennteam.com/showflat.php?Cat=0&Number=152118&an=0&page=2#152118
It does feel more GT than the C2S... but the understeer is not comparable to the 996 C4S , more like 996 C4, maybe even a little bit less...
www.rennteam.com/showflat.php?Cat=0&Number=152118&an=0&page=2#152118
Re: C4 & C2 Image Comparison
Could anyone email me or post here this entire article from "Excellence" magazine, the November issue?
"Road Test: 2006 Carrera 4 & 4S Cabriolet
The return of the world's ultimate four-seasons Cabriolet, and it's a stunner.
By Ian Kuah"
I'm a new subscriber to "Excellence" but have been notified my sub will not begin until the December issue. I'd hate to miss this article on the 06 Cabs as mine is "ON VESSEL".
Thanks.
"Road Test: 2006 Carrera 4 & 4S Cabriolet
The return of the world's ultimate four-seasons Cabriolet, and it's a stunner.
By Ian Kuah"
I'm a new subscriber to "Excellence" but have been notified my sub will not begin until the December issue. I'd hate to miss this article on the 06 Cabs as mine is "ON VESSEL".
Thanks.
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