How to fix the 718 RS wheels bouncing?
03-30-2024 | 01:48 PM
#46
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agree 100% one of the advantages of PCCB, significant advantage of PCCB reduces the unsprung weight and therefore allows the spring and shock to respond faster...
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Westcoast (03-30-2024)
03-30-2024 | 02:34 PM
#47
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Larry Cable (03-30-2024)
03-30-2024 | 03:32 PM
#49
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Agree. This is explained fairly well by the EE guy. Along those same line, magnesium wheels would also help. My SRS order has locked. I choose PCCB but not mag wheels. This news of the 718 SRS wheels bouncing makes me a bit more interested in purchasing aftermarket mag wheels to accompany my PCCB.
https://www.youtube.com/watch?v=VBd9y3mxzCM
https://www.youtube.com/watch?v=VBd9y3mxzCM
But soon I will be reducing the wheels weight even further with Apex VS5-RS on my Spyder, these are also available in CL for the RS.
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Larry Cable (03-30-2024)
03-30-2024 | 03:51 PM
#50
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FYI, the OEM suspension *are* (already a) coilover design.
there are a few variables you can play with:
- spring rates
- shock valving (to "match" the chosen spring rate)
- low speed compression
- high speed compression
- low speed rebound
- high speed rebound
both PASM and DSC dynamically adjust the compression and rebound.
with any (adjustable) suspension technology (DSC or not) the practitioner must be experienced in chosing the appropriate springs and damping, and then be able to
further tune that setup via the adjustment of the high/low compression & rebound ...
this is not plug and play and requires a skillset only acquired either on the track or at a suspension/vehicle manufacturer...
generally low speed is for tuning in corners, high speed is for tuning "bumps"...
there are a few variables you can play with:
- spring rates
- shock valving (to "match" the chosen spring rate)
- low speed compression
- high speed compression
- low speed rebound
- high speed rebound
both PASM and DSC dynamically adjust the compression and rebound.
with any (adjustable) suspension technology (DSC or not) the practitioner must be experienced in chosing the appropriate springs and damping, and then be able to
further tune that setup via the adjustment of the high/low compression & rebound ...
this is not plug and play and requires a skillset only acquired either on the track or at a suspension/vehicle manufacturer...
generally low speed is for tuning in corners, high speed is for tuning "bumps"...
I think what he meant here was motorsport grade dampers, rather than the coil-over design in general. The quality of the damping is just better on a high end motorsport damper compared to the stock PASM ones.
03-30-2024 | 03:51 PM
#51
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03-30-2024 | 03:52 PM
#52
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I dont disagree ... only trying to add some value ... and insight into the challenge of "going aftermarket" YMMV
03-30-2024 | 03:56 PM
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The Apex wheels IMO are definitely a game changer. They made more of a difference than what I was expecting, especially on the front-end. I would have done those before the Kline Exhaust had I known how much they improved things.
The extra unsprung mass reduction is great for lessening the work the dampers have to do, but equally as impressive is how much more direct and stable the front-end is. That extra width of the wheels and sticking with stock size tires (which stretches the tire a bit more than stock) really can be felt.
When you turn in now, the outside front wheel doesn't feel like it is folding in on its self any longer, It takes a set and just reacts. Gives the front-end much more authority. That is how it should have been done from the factory.
The extra unsprung mass reduction is great for lessening the work the dampers have to do, but equally as impressive is how much more direct and stable the front-end is. That extra width of the wheels and sticking with stock size tires (which stretches the tire a bit more than stock) really can be felt.
When you turn in now, the outside front wheel doesn't feel like it is folding in on its self any longer, It takes a set and just reacts. Gives the front-end much more authority. That is how it should have been done from the factory.
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03-30-2024 | 05:41 PM
#55
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https://en.wikipedia.org/wiki/List_o...eife_lap_times
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
Last edited by alcc; 03-30-2024 at 05:42 PM.
03-30-2024 | 05:46 PM
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https://en.wikipedia.org/wiki/List_o...eife_lap_times
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
That is a case of you just getting used to the handling characteristics. Your first impressions is the key point here.
Most can get "used" to something with enough seat time and learn to drive around it. IMO you should NOT have to drive around an issue like that for the price that Porsche charges for these things.
03-30-2024 | 06:16 PM
#57
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That is a case of you just getting used to the handling characteristics. Your first impressions is the key point here.
Most can get "used" to something with enough seat time and learn to drive around it. IMO you should NOT have to drive around an issue like that for the price that Porsche charges for these things.
Most can get "used" to something with enough seat time and learn to drive around it. IMO you should NOT have to drive around an issue like that for the price that Porsche charges for these things.
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03-30-2024 | 06:25 PM
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https://en.wikipedia.org/wiki/List_o...eife_lap_times
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
We all know the N'ring is a particularly tough track for the 4RS. Still, and the point should be, the 4RS put up incredible lap times by any stretch of the imagination, especially given its relative lack of rubber compared to the GT3 and "supercars." Look at the factory time (7:04), not just the Manthey time (6:58). Does not look to me that's possible for a car whose wheels "bounce." Note: I am not an uncritical fan boy.
Jeremy Clarkson famously said that so many cars are ruined because they kept testing them at the N'ring.
When I got my GTS 4.0 I was surprised by the underdamped rebound. After a year, somehow the suspension feels much more settled. My 4RS felt good (enough) to me from day 1, especially on firm setting. After a year, it, too, feels even more more settled. I have never felt "wheel bounce." Note: I do have both PCCB and mag wheels.
Ive been lapping the 'Ring for the last 20 years, and in both a GT4RS and a 992GT3 most recently - the GT3 is significantly more planted than the 4RS on the bumpy sections ... its a matter of degrees but the rear suspension of
the 4RS lets it down in comparison - and when you are doing 150mph down Fuchsrohre you do not need rear instability the car moves laterally because the suspension is not keeping the rubber on the road.
this is my experience ... YMMV
03-30-2024 | 06:43 PM
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Not sure I understand your last statement—are you suggesting that for proper track use, one needs to change the entire suspension set? Are your tracks particularly rough and bumpy? That sounds horrible if that’s the case.
I seem to do just fine with the stock suspension—on public roads and more importantly, on my local tracks—curbs and all. Of course with a proper alignment and some toe links for additional rear camber. I will say that this RS is my fourth Cayman, so maybe I’ve gotten used to its dynamic character and limitations, and have learned to work with it. It’s rewarding that way.
For those that primarily use their car on the street, and have to deal with bumpy, uneven pavement all the time, I understand that everyone’s comfort level with what feels safe and fast is highly personal. I’m all for modding the car to suit one’s tastes, especially as no car can be all things to all people.
But to claim that the GT4 RS needs an entirely different suspension setup to perform well on track is just false.
I do think that aftermarket suspension options, like MCS and KW can improve performance for both street and track. But unless your track is particularly horrible, surface-wise, I don’t find it an essential upgrade to put in fast lap times. I’d rather invest the $$$ in more track time, tires, brakes, and insurance.
I seem to do just fine with the stock suspension—on public roads and more importantly, on my local tracks—curbs and all. Of course with a proper alignment and some toe links for additional rear camber. I will say that this RS is my fourth Cayman, so maybe I’ve gotten used to its dynamic character and limitations, and have learned to work with it. It’s rewarding that way.
For those that primarily use their car on the street, and have to deal with bumpy, uneven pavement all the time, I understand that everyone’s comfort level with what feels safe and fast is highly personal. I’m all for modding the car to suit one’s tastes, especially as no car can be all things to all people.
But to claim that the GT4 RS needs an entirely different suspension setup to perform well on track is just false.
I do think that aftermarket suspension options, like MCS and KW can improve performance for both street and track. But unless your track is particularly horrible, surface-wise, I don’t find it an essential upgrade to put in fast lap times. I’d rather invest the $$$ in more track time, tires, brakes, and insurance.
Our complaints are very minor here and we're just being nit picky but it shows how the 4RS is a harder car to drive and that makes people want to change parts instead of becoming better drivers to learn how to properly use it. If this was not the case it would not be setting the lap times it does stock at the Ring or Car and Drivers Lightning lap in the hands of advanced drivers.
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