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      02-22-2017, 04:26 AM   #507
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Quote:
Originally Posted by redux View Post
Shhhhh! You've got to let people find out things themselves. Giving hints and seeing where people take it makes the forum far more entertaining.

Exactly !!

Imagine his influence on the F8x forum versus the GTS forum!!

I am a very avid follower of CanAut on the suspension sub forum .... and I know I'm quicker because of his input ✔️✔️✔️
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      02-22-2017, 05:23 AM   #508
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Quote:
Originally Posted by paradoxical3 View Post
Aha, you've found the answer to why the GTS steering sucks! A slightly wider front hub carrier!

This is really devolving into the ridiculous.


Don't put words in my mouth. I cannot comment on the M4 GTS' steering feel because I have not driven one. I am not stating if those changes make the steering better or worse. What I did is correct a misstated fact where there are indeed difference between the GTS and base M3/4 front suspension geometry. But if you think that has no effect one steering feel an feedback, I suggest you look-up scrub radius, caster and Ackerman angle to start with.
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Last edited by CanAutM3; 02-22-2017 at 06:41 AM.
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      02-22-2017, 09:34 AM   #509
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Quote:
Originally Posted by CanAutM3 View Post


Don't put words in my mouth. I cannot comment on the M4 GTS' steering feel because I have not driven one. I am not stating if those changes make the steering better or worse. What I did is correct a misstated fact where there are indeed difference between the GTS and base M3/4 front suspension geometry. But if you think that has no effect one steering feel an feedback, I suggest you look-up scrub radius, caster and Ackerman angle to start with.
Track has such little difference in steering feedback that it is absurd to mention it to explain the huge gulf in steering feel the reviewers claim between the GTS and the M2 and M4. The second someone puts spacers or different wheels on either car there is a greater difference in front track than the hub carrier. You do not see people making threads saying "I put spacers on my car and lost all steering feel!" The same goes for KW coilovers - nobody says, "I just put Clubsports on my car and now I lost road texture feel!"

The entire point of my posting is to show how hyperbolic reviewers are being with proclamations like the M4 GTS has the worst steering feel ever, while they say the M2 has the best steering feel of any current M car. A few mm in track width is not going to cause such a wide gulf in reviews. It is absolutely nothing compared to an entirely different power steering map that literally changes the required steering angle and weight on the car to achieve a certain corner radius.

Of course, all of this could be confirmed if you guys with base M4s simply tried the coding change I suggested and switched your power steering map to that of the M2/GTS. You will notice a difference; I have done it for several local cars and it's immediately noticeable. If you have such a sensitive butt that you can detect a few mm difference in track width, this will be like hitting you over the head with a sledgehammer.

Last edited by paradoxical3; 02-22-2017 at 09:44 AM.
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      02-22-2017, 10:31 AM   #510
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Quote:
Originally Posted by paradoxical3 View Post
Track has such little difference in steering feedback that it is absurd to mention it to explain the huge gulf in steering feel the reviewers claim between the GTS and the M2 and M4. The second someone puts spacers or different wheels on either car there is a greater difference in front track than the hub carrier. You do not see people making threads saying "I put spacers on my car and lost all steering feel!" The same goes for KW coilovers - nobody says, "I just put Clubsports on my car and now I lost road texture feel!"

The entire point of my posting is to show how hyperbolic reviewers are being with proclamations like the M4 GTS has the worst steering feel ever, while they say the M2 has the best steering feel of any current M car. A few mm in track width is not going to cause such a wide gulf in reviews. It is absolutely nothing compared to an entirely different power steering map that literally changes the required steering angle and weight on the car to achieve a certain corner radius.

Of course, all of this could be confirmed if you guys with base M4s simply tried the coding change I suggested and switched your power steering map to that of the M2/GTS. You will notice a difference; I have done it for several local cars and it's immediately noticeable. If you have such a sensitive butt that you can detect a few mm difference in track width, this will be like hitting you over the head with a sledgehammer.
i will be doing the GTS coding today on my M4, and i will be able to compare the feel to my GTS, the cars currently are 2 completely different cars and my Base M4 has the KW Clubsport 2 ways

while i doubt the steering will bring the car itself close to my GTS, i am still exciting for the better steering feel
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      02-22-2017, 10:56 AM   #511
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Quote:
Originally Posted by Alex@AUTOcouture View Post
i will be doing the GTS coding today on my M4, and i will be able to compare the feel to my GTS, the cars currently are 2 completely different cars and my Base M4 has the KW Clubsport 2 ways

while i doubt the steering will bring the car itself close to my GTS, i am still exciting for the better steering feel
Awesome, will be especially interesting to see your thoughts with the clubsports on there.

If you have the latest psdzdata there is a new power steering variant for the M2 CS too, I have not tried that yet. But it is separate from the M2/GTS variant so perhaps it's worth exploring as well.
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      02-22-2017, 11:05 AM   #512
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Quote:
Originally Posted by paradoxical3 View Post
Awesome, will be especially interesting to see your thoughts with the clubsports on there.

If you have the latest psdzdata there is a new power steering variant for the M2 CS too, I have not tried that yet. But it is separate from the M2/GTS variant so perhaps it's worth exploring as well.
interesting, well the clubsports in the gts arent just normal ones form kw, just at a quick glance you can see the springs are from eibach,

Im not going to start getting into a comparison here, but the gts feels and drives like a completely different car, its hard to explain without driving it, but it feels like a different car altogether, its perfectly balanced and put together
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      02-22-2017, 06:53 PM   #513
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Quote:
Originally Posted by Alex@AUTOcouture View Post
interesting, well the clubsports in the gts arent just normal ones form kw, just at a quick glance you can see the springs are from eibach,

Im not going to start getting into a comparison here, but the gts feels and drives like a completely different car, its hard to explain without driving it, but it feels like a different car altogether, its perfectly balanced and put together
I would say the kw on the gts uses the shock/strut body of the clubsport and that'd about the only thing they share in common. The spring seats, front top hat and rear top Mount is completely different.

It's a feeling that is hard to explain and only those who have driven both will know.
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      02-22-2017, 07:07 PM   #514
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Quote:
Originally Posted by M4_GTS View Post
I would say the kw on the gts uses the shock/strut body of the clubsport and that'd about the only thing they share in common. The spring seats, front top hat and rear top Mount is completely different.

It's a feeling that is hard to explain and only those who have driven both will know.
I'm sure the actual valving is different as well, probably to BMW's spec instead of KW's.
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      02-22-2017, 08:39 PM   #515
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Quote:
Originally Posted by paradoxical3 View Post
Track has such little difference in steering feedback that it is absurd to mention it to explain the huge gulf in steering feel the reviewers claim between the GTS and the M2 and M4. The second someone puts spacers or different wheels on either car there is a greater difference in front track than the hub carrier. You do not see people making threads saying "I put spacers on my car and lost all steering feel!" The same goes for KW coilovers - nobody says, "I just put Clubsports on my car and now I lost road texture feel!"

The entire point of my posting is to show how hyperbolic reviewers are being with proclamations like the M4 GTS has the worst steering feel ever, while they say the M2 has the best steering feel of any current M car. A few mm in track width is not going to cause such a wide gulf in reviews. It is absolutely nothing compared to an entirely different power steering map that literally changes the required steering angle and weight on the car to achieve a certain corner radius.

Of course, all of this could be confirmed if you guys with base M4s simply tried the coding change I suggested and switched your power steering map to that of the M2/GTS. You will notice a difference; I have done it for several local cars and it's immediately noticeable. If you have such a sensitive butt that you can detect a few mm difference in track width, this will be like hitting you over the head with a sledgehammer.
Track width in itself has little incidence on steering feel and feedback. However changes in wheel offset that alter the scrub radius and/or Ackerman angle can have a noticeable impact on steering feel and feedback. I am one that does not like the effect of spacers on the front axle. I tried 12mm spacers on my E92 and hated how it killed steering feel. The reason you don't see many complaining about this is that the majority of drivers are not sensitive enough to notice the difference. Further, from the alignment sheets I have seen posted on the forum, it seems the GTS has more caster than the base M3/4. This also has an impact on steering feedback. Steering feel is born in the geometry of the front suspension, not in the EPS programming. The programming can be made to filter less and transmit more, but it cannot be made to create feel and feedback that is not there to start with. Maybe we can get Racer20 to provide more insight.
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Last edited by CanAutM3; 02-22-2017 at 08:50 PM.
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      02-22-2017, 10:48 PM   #516
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Quote:
Originally Posted by CanAutM3 View Post
Track width in itself has little incidence on steering feel and feedback. However changes in wheel offset that alter the scrub radius and/or Ackerman angle can have a noticeable impact on steering feel and feedback. I am one that does not like the effect of spacers on the front axle. I tried 12mm spacers on my E92 and hated how it killed steering feel. The reason you don't see many complaining about this is that the majority of drivers are not sensitive enough to notice the difference. .
Your bolded statement here is exactly why I said it's absurd to attribute the gulf in reviews due to things like a different hub carrier and Ackerman angle. I am agreeing with you here. That is kind of the whole crux of my argument.

95% of posters and reviewers aren't going to notice a change in Ackerman angle because they don't have enough experience to. It can be a subtle difference. 95% of posters will notice a change in EPS mapping because it affects more obvious parameters like steering weight. This goes either way - for better or for worse.
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      02-22-2017, 10:51 PM   #517
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Quote:
Originally Posted by paradoxical3 View Post
Your bolded statement here is exactly why I said it's absurd to attribute the gulf in reviews due to things like a different hub carrier and Ackerman angle. I am agreeing with you here. That is kind of the whole crux of my argument.

95% of posters and reviewers aren't going to notice a change in Ackerman angle because they don't have enough experience to. It can be a subtle difference. 95% of posters will notice a change in EPS mapping because it affects more obvious parameters like steering weight. This goes either way - for better or for worse.
We are in agreement
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      02-27-2017, 08:30 PM   #518
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I had my dealer change my Ackerman angle to the same setting the DTM cars use, and I notice a huge increase in corner exit feel!! I'd do it myself but the gauge and clips used to make the adjustment costs nearly $1200! (Side benefit is that brake dust is also more evenly distributed now - nice)
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