Rear Axle Steering

kwrudy123

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Hello there,
i have a Taycan 4s in order and still have sometime to lock the spec. i am thinking to order the RAC but i am not sure if it is worth it and whether i will feel the difference in driving and parking. even some Porsche salesmen said it is not worth it unless you go to track. i tried to find some videos in youtube but i could't find anything for Taycan . i would be very thankful in guiding me on this and if some owners who have the option can demonstrate in videos to show the difference , that would be great. thanks in advance.
I just took delivery of my 2nd Taycan Turbo, a 2021 with rear axle steering and PDCC (Porsche Dynamic Chassis Control). My first Taycan (a 2020 that I traded with 11,500 miles on it) did not have the real axle steering, nor the PDCC. Being able to compare the two cars back-to-back, I can easily say that the 2021 with RAS and PDCC handles significantly better than the 2020. The steering is way more precise and the turns tighter with RAS. You can almost sense the car turning more around the center of its axis with RAS than what I felt with the 2020 and the car merely following its front wheels in turns. Also the PDCC does an amazing job at keeping the car level in higher speed sweeps and turns. Those two options, on what was otherwise the exact same car has made a huge difference in the quality and sportiness of the driving experience. Well worth it!
 

PEV1

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I have RWS on my 4S and besides a noticeable enhancement to my previous e-Hybrid Panamera 4S and excellent parking manoeuvring, I am also able to eliminate 3point U-turns on inner city streets. Very handy and worth the spend in my view.
 

W1NGE

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If you want to see proper RAS in action watch the video of the new S class parallel parking.

The implementation on the Taycan, 911 etc affords something like 2.4 degrees of turn which is almost invisible to see. Not sure what the reason for this is but for parking you might expect something more.

I have RAS on my Taycan and did not have it on my Panamera which it replaced. I have a parking space which is about 6.5m pillar to pillar (so tight) and to be honest I could park the Panamera just as easily as the Taycan which is a smidgen shorter.

For high speed roads with sweeping bends then RAS might just offer something worth having but hard to say for sure given the handling dynamics of the car to begin with.
 

andix

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I test drove both with and without.
It makes quite a noticeable difference, especially when maneuvering at lower speeds.
Actually, the Taycan feels like a small car!
 


Tay Tay

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If you want to see proper RAS in action watch the video of the new S class parallel parking.

The implementation on the Taycan, 911 etc affords something like 2.4 degrees of turn which is almost invisible to see. Not sure what the reason for this is but for parking you might expect something more.
Someone (maybe you!) keeps on bringing up the S-class. True, they managed to reduce their turning circle by 10% (from '20 to '21 MY) whereas RAS on the Taycan reduces it by only 7%. However, that 10% reduction on the S-class gets it to the same turning circle as... a Taycan without RAS. LOL. So it still won't feel particularly tight whereas a Taycan with RAS would DESTROY the turning circle of an A-class!
 

W1NGE

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Someone (maybe you!) keeps on bringing up the S-class. True, they managed to reduce their turning circle by 10% (from '20 to '21 MY) whereas RAS on the Taycan reduces it by only 7%. However, that 10% reduction on the S-class gets it to the same turning circle as... a Taycan without RAS. LOL. So it still won't feel particularly tight whereas a Taycan with RAS would DESTROY the turning circle of an A-class!
Perfect, you missed my point entirely!

Watch the video and note the dramatic turn of the rear wheels. The angle I quoted relates to the turn angle of the axle and not the percentage of reduced turning circle ;)
 


Tay Tay

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Perfect, you missed my point entirely!

Watch the video and note the dramatic turn of the rear wheels. The angle I quoted relates to the turn angle of the axle and not the percentage of reduced turning circle ;)
Perfect, you missed MY point entirely. The percentage the turning circle is reduced is also 10 (%). Who cares if the rear wheel turns a lot more if it’s only giving you an extra 3% and it’s still way worse than a Taycan?
 

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Are you guys familiar with "bump steering"?
I have RAS and now that I am familiar with the car's behavior, I notice quite some bump steering at lower speeds on uneven roads and put holes...
It's feels like unsettling the car quite a lot imho.
On higher speeds it's (obviously) not that noticable but it's there.
I wouldn't spec it again, only to have a smaller turning circle.
 
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oalsaker

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Are you guys familiar with "bump steering"?
I have RAS and now that I am familiar with the car's behavior, I notice quite some bump steering at lower speeds on uneven roads and put holes...
It's feels like unsettling the car quite a lot imho.
On higher speeds it's (obviously) not that noticable but it's there.
I wouldn't spec it again, only to have a smaller turning circle.
I presume you are talking about the Ackerman effect which is due to a different turning radius of the front wheels at full lock. If so, it would be unaffected by RWS since the steering geometry of the front wheels will be exactly the same. It might even be improved if you can avoid full lock by using RWS.

I haven't had any of this with my 20" wheels, so I guess it's the price you pay for the sexy 21" wheels.
 

wemct

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I haven’t had this either with my 21 inch Mission e wheels.
 

Dee

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I presume you are talking about the Ackerman effect which is due to a different turning radius of the front wheels at full lock. If so, it would be unaffected by RWS since the steering geometry of the front wheels will be exactly the same. It might even be improved if you can avoid full lock by using RWS.

I haven't had any of this with my 20" wheels, so I guess it's the price you pay for the sexy 21" wheels.
No.
I mean driving straight where a bump/hole forces the rear wheels to change geometry due to the RAS set-up, both in compression and rebound.
Every design has it's disadvantages and advantages.
I prefer multilink without RAS.
The Taycan doesn't have that, it's double wishbone unfortunately.
 
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feye

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Every design has it's disadvantages and advantages.
Usually the case.

I mean driving straight where a bump/hole forces the rear wheels to change geometry due to the RAS set-up, both in compression and rebound.
We have loads of bumps here, but cannot understand this issue. How do you need to drive to make it most pronounced, so I can experience it?

Could it be that because you have PDCC, that you notice something I do not have? Did Porsche miss something in their extensive testing phase?
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