991.2 GT3 sell now or keep dilemma
Discussion
Cheib said:
I'm amazed at that...split was pretty equal for a long time only in the last few months has it started to move towards more PDK's.
the indication that the 992 gt3 will initially only be pdk is a major factor ,plus over an extended period of time the manual will be more sought after due to a lack of other manual options when buying these types of cars.franki68 said:
Cheib said:
I'm amazed at that...split was pretty equal for a long time only in the last few months has it started to move towards more PDK's.
the indication that the 992 gt3 will initially only be pdk is a major factor ,plus over an extended period of time the manual will be more sought after due to a lack of other manual options when buying these types of cars.Cheib said:
Finally got my Weiss Gold FI-R’s with the Cup 2 Connect’s on the car...my OEM wheels have got PS4S so those will be going back on in a month or so. Maybe the placebo effect but I do think the car rides differently and maybe the steering is a bit lighter.
They look great C.Hope your furloughed gardener doesn't object to your parking on the lawn.....
Cheib said:
Hadn’t heard that about the 992....Porsche love making things difficult for people. Make the bloody cars in every spec that you intend to make available from Day 1.
eWell said.. I can’t see Porsche restricting gearbox to PDK for early run cars? Makes no sense as they are offering manual on base 992 & 718
Cheib said:
Spyder75 said:
Defo not placebo btw.
I was surprised by the difference to be honest...I am definitely not a PH driving god but have had the car for 2 1/2 years so know it pretty well at this stage. That’s usually the key benefit to ride and handling.
Koln-RS said:
Cheib said:
Spyder75 said:
Defo not placebo btw.
I was surprised by the difference to be honest...I am definitely not a PH driving god but have had the car for 2 1/2 years so know it pretty well at this stage. That’s usually the key benefit to ride and handling.
From JCR’s website.
Cheib said:
About 2.5 KG per wheel....not that much but it’s also 25% of the wheel weight (excluding tyre obviously) . I’ve read in the past that there’s some kind of multiplier for rotational unsprung weight but I have no idea of the physics/mathematics that support that
From JCR’s website.
That will be what makes (the majority of) the difference. I recall many years back comparing steering and ride of a steel vs. ceramics equipped 997. The effects were what you describeFrom JCR’s website.
[quote=Cheib]
About 2.5 KG per wheel....not that much but it’s also 25% of the wheel weight (excluding tyre obviously) . I’ve read in the past that there’s some kind of multiplier for rotational unsprung weight but I have no idea of the physics/mathematics that support that
To Calculate Un sprung weight to a real weight saving generally x4 so real World 2.5kgs Un Sprung is like saving 10kgs in other areas
About 2.5 KG per wheel....not that much but it’s also 25% of the wheel weight (excluding tyre obviously) . I’ve read in the past that there’s some kind of multiplier for rotational unsprung weight but I have no idea of the physics/mathematics that support that
To Calculate Un sprung weight to a real weight saving generally x4 so real World 2.5kgs Un Sprung is like saving 10kgs in other areas
Juno said:
Cheib said:
About 2.5 KG per wheel....not that much but it’s also 25% of the wheel weight (excluding tyre obviously) . I’ve read in the past that there’s some kind of multiplier for rotational unsprung weight but I have no idea of the physics/mathematics that support that
To Calculate Un sprung weight to a real weight saving generally x4 so real World 2.5kgs Un Sprung is like saving 10kgs in other areas
no one really knows, the maths are all over the place on forums for 30 years regarding this. To Calculate Un sprung weight to a real weight saving generally x4 so real World 2.5kgs Un Sprung is like saving 10kgs in other areas
1x, 2x, 4x, even 6x the weight, but really you are doing it for rotational gains with less mass, over what you would have to save vs static weight in a car.
so sus feel, steering feel etc over swapping out a battery as an example. you won;t feel a battery swap out and that's way more saving, you do feel a change with wheels.
Koln-RS said:
Cheib said:
Spyder75 said:
Defo not placebo btw.
I was surprised by the difference to be honest...I am definitely not a PH driving god but have had the car for 2 1/2 years so know it pretty well at this stage. That’s usually the key benefit to ride and handling.
IMI A said:
Less momentum from gyroscopic effect with lighter wheels and light pccb. Makes a difference its not placebo. The heavier the wheel the less it wants to move from its orientation/axis of rotation
Yep, it's quite a difficult thing to explain. I remember doing this experiment at school (it's the one where you hold a spinning wheel on a chair that spins)https://youtu.be/5cRb0xvPJ2M
A spinning object, in this case a wheel, is more difficult to turn as there are more particles in the spinning mass. A spinning heavy wheel has angular momentum and to change that momentum you have to apply torque. In the case of the chair clip above, the torque is applied by your arms to change the direction of angular momentum. In a car, the torque is applied by the steering.
A lighter spinning wheel has less angular momentum and is easier to redirect.
I took the PCBB's off my 997.1 GT3, as they're great for road use, but not up to track. replacing them with steels of the same diameter, you definitely could perceive changes in ride and steering, aside obviously from braking performance.
The moment of inertia is 'r' squared, so weight saved at the rim of the wheel will have greatest effect. I'd be surprised if the difference weren't apparent.
The moment of inertia is 'r' squared, so weight saved at the rim of the wheel will have greatest effect. I'd be surprised if the difference weren't apparent.
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