Yargk

I test drove a 996.2 GT3 and a 997.1 GT3 RS back to back the other day. It seemed that the RS had less feeling from the suspension, whereas with the 6 I could feel every jiggle. The 6 drove like an old Porsche that had everything made new and evolved and improved, whereas the 7 seemed like something different. I actually liked the 6 more, but I need more time in the 7 to really judge because it felt less familiar, if that makes any sense.

Have any others come to the same conclusion? Is it the PASM? If so, how does the 7.2 compare?

Paseb

don't quote me on that since ive never driven a 997 gt3,

but 997gt3 doesnt have the raw and the stiffness at all off the 996 gt3.

996 gt3 drives like a tractor. your going to the war with it, you know..

well, thats how i feel with it

997gt3north

Having driven both, I think the biggest difference is not the suspension per say but the the entire chassis. The 997 chassis is what makes the car 'feel' as different as it does. The words 'more planted', 'can't feel it as much', 'isolated', 'less raw', 'go to war with it, etc etc etc - it has been said a million ways - but what you are feeling is that the 997 chassis is substantially stiffer than the 996 - in the 996, the entire car bends more as it absorbs bumps so you feel it - in the 997, the chassis bends less, isolates the driver from this bending and the suspension does it's work without you feeling it as much. You can then add that the PASM shocks are making small adjustments in either of the 2 modes but those are small effects - if you put the car in Firm mode it feels more 996 like but still different - the difference is the chassis.

If you asked about the difference between the 997.1 and 997.2 gt3 cars, then the difference is the suspension (spring rates, shock dampening, PASM controller)

IPguy

what are the torsional stiffness numbers of each chassis?

Leigh2

The 6GT3 chassis with the lack of traction control and its ABS system adds up to a very enjoyable drive. The chassis turns in very well and is quite controllable when sliding around at the limit. No question that the 997 chassis/engine is faster though. The 7GT3 is also more comfortable on the street and on the track the extra power is quite apparent.
The 7GT3 has some inherent issues though that eventually show up. The TC if left on wears the rear pads/rotors quite quickly and the ABS system has some issues with track driving that can show up at awkward times (search "ice mode"). It is also difficult to dial out the "push" the 7 chassis seems to have, although most of my experience has been with cups. I have always liked the handling of the 6 better even though it's all happening at (slightly) slower speeds.
The 7.2 is faster yet with even more engine and tire, plus some suspension fine tuning. It's also more comfortable on the street but still works well on the track without having to punt the spring rate upstairs. Overall I still think the 6GT3 is by far the best bang for your Porsche $'s with tremendous "feel" at speed. The 7.1 then the 7.2 are definitely quicker and more refined and comfortable but at an accordingly higher price point.

85Gold

Not sure where you get your 997 chassis is stiffer than the 996 chassis. The 996 uses a seam welded, 996 C4 narrow body, chassis. Never read in any literature that the wider 997 was stiffer. Now the suspension is definently different and it isn't just PASM.

Peter

997gt3north

I'll try and find it - but when the car first came out the numbers were quoted - 30% stiffer rings a bell but I'm pulling that from thin air - it could be lower but it is stiffer for sure.

To me it was very obvious. I went from learning in a 997gt3, having never been in a 996gt3, to then getting a few rides and then driving a 996gt3. The 7s chassis isolates you so much more from the feel of the track - which makes the 6 a gem in many people's opinion.

It is a ridiculous analogy but wood tennis racket versus first generation graphite - if you were a tennis player during the cross over you would know what I mean McEnroe volleying vs Lendl - that's 6vs7 for the old tennis players.

LVDell

I did a fairly extensive writeup and comparison between the 6 and 7 GT3 having owned both. Do a search for my thread. They are VERY different cars.

HiWind

I'm driving a McEnroe?!

agtlaw

Actually a C2 body with C4 floorpan and minimal seam welding.

Mikelly

As much as I love my new to me 6gt3, I can't imagine Porsche not making any of the follow-on GT3s stiffer and better in the chassis/suspension department. Not having driven anything newer than a 997.1 GT3, I can't speak to the "perceptions" people have as to which is better or more well suited for them.

Mike

Suns_PSD

Once a chassis is made really stiff, the cars don't need to be nearly as stiffly sprung for the suspension to operate correctly.

The Lotus is suspended very softly and it's a demon in the turns.

HiWind

some one (clever) posted the numbers for the chassis stiffness of 996 1.2 - 997 1.2 - 991 recently
- anyone remember seeing that post in the last month or so? Cant find it. Thanks!

911SLOW

I posted this in the cup section a few months ago


"The C4 was not more rigid than the C2. This is a myth.

For example all 911 Carrera variants included a range of reinforcements introduced on MY02 ( door sills, roof frame and seat wells).
All cars, compared with their predecessors, had an equal 25% improvement in static strength and torsional rigidity.


The main reason that the 996CUP / 996GT3 used the body from the 996 Carrera 4 was the fact that this was the only body which could be used to meet the fuel tank requirements for a range of race series (FIA GT Championship, etc).
Under these regulations, no part of the fuel tank may extend beyond the forward-most point of the front wheel.

The resulting tank in the street (homologated car) offered a refill volume of 89 litres. This additional capacity was achieved solely by extending the tank into the front differential cavity, without any modification to the shell.

The GT3 and cup tubs (apart from the integrated cage difference_)also had some common key modifications over the std C4.
These included additional welded sections on the rear cross-member, that provided a more even distribution of loads from the engine and gearbox, and a modified rear bulkhead. "



About the stiffness of a 996 GT3 vs a 997 GT3, the torsional rigidity was increased by 8 % and its flexural rigidity by 40 %.

HiWind

thanks John! NIce to see your avatar staying stable for more than a week .... hmmm ... is that a pokemon face is see looking out of that shadow?

I found it here ... in that awesome 69 with a GT3 engine build thread awesome

According to his estimates of the different models stiffness:

'88 911 7k nm/deg (measurement by burgermeister)
964 11.5k nm/deg (993 was 20% stiffer)
993 13.9k nm/deg (996 was 45% stiffer)
996 20.1k nm/deg (Excellence was Expected p.1381)
997 33k nm/deg
991 40k nm/deg (porsche used 20% torsionally stiffer as a design target, has claimed "up to 25% stiffer")

sound about right? is there a good place to read about how they do that? Thanks Boss!