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      07-26-2020, 01:04 PM   #45
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Quote:
Originally Posted by FrostyDC4 View Post
Do you have a lot of body lean up front with the sway bar delete? Asking because the fast 350Z/370z drivers either run a big bar up front and/or run without a rear sway bar.
The lean is actually pretty substantial. It can feel a little clumsy on tight tracks, but the gain in grip is undeniable. Just turning the damping up a click or two solves the wallowing feeling though. I'll have to find a picture of it in a turn from the outside...

This won't directly translate to a 350/370Z, as they have a very different front suspension setup (Double Wishbone vs. our MacPherson Strut). Their geometry may have a less favorable camber change characteristic than our struts, which would necessitate that they run a big front sway bar to keep the suspension in it's optimal location in the turns. But, I don't know that much about those cars to say for sure. Unlikely, because that tends to be the big advantage of a double wishbone, and it would be dumb of Nissan to handicap the chassis like that.
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      09-29-2020, 11:53 AM   #46
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Quote:
Originally Posted by gmx View Post
On the 718 GT4 (SRO), the KW could and are more likely to be competitions rather than clubsport. THey also look like aluminium bodies?

There was 1M here using this. Actually it was the white one posted on this forum:
https://www.1addicts.com/forums/showthread.php?t=684308

They ended up modifying it a lot (esp front top plate) speaking to someone buying parts from their retired car. They've since moved on to racing F80s since the pure (we don't get really get strippers here) comes in under MSRP making it eligible. One of the 135i (same team or a competitor ran it, don't remember) competition dampers ended up on this member's car:
https://www.1addicts.com/forums/show....php?t=1302309
i came to this thread to learn a bit more about spring rates and what people run on these cars, and found it funny to see the Lynton car mentioned especially "esp the front top plate". it was... interesting when they handed it to me lol. i'll attach a photo for everyone else as i couldn't see one in the original thread (though it looks like this is a different set of dampers to that specific set they first built with the car. I'm guessing they came off the pink one?)

i ended up buying their Kw competitions last year as they moved to a custom setup by some local guys so they could have on-track support and the price was too good to pass up (and has since been a terrible decision but that's another story and my own fault lol). at least 12 months ago, it wasn't retired at the time. Facebook leads me to believe it was sold (or something) and raced under "fierce racing" with a bright orange paint job, and I'm guessing by the parts coming off the car through lyntons, they continued to support and work on them. EDIT: well this worked out well, turns out they had a part for sale that i really needed. nice. oh and looks like they have one side of the black shocks for sale you can see in that thread, but with a standard camber setup. wonder what happened to the other side.

FWIW, they ran 600/900lb springs and it's what i'll be starting with as such w/standard sways. i'm changing so much all at once that i'm pretty lost as to whether it's all going to work and how much fiddling i'll have afterwards. i'm guessing "a ton". will report back with how it feels if i remember to.



though i have a feeling they ran the plates flipped L-R judging by some wear, putting them in tomorrow so i'll find out how it sits soon enough.

Last edited by flinchy; 09-29-2020 at 12:45 PM..
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      10-06-2020, 09:00 AM   #47
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does anyone make adjustable front swaybars that will go softer than stock?

I have ran with the front disconnected and I liked it but I would prefer to retain some adjustability
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      10-07-2020, 09:15 PM   #48
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Quote:
Originally Posted by imported_mega View Post
does anyone make adjustable front swaybars that will go softer than stock?

I have ran with the front disconnected and I liked it but I would prefer to retain some adjustability
Not that I am aware of, all of the adjustable bars I found when looking started stiffer than stock. Your probably in the world of a custom fabricated bar for what your wanting.

Easier to head in the direction of handling balance your after by doing a stiffer rear bar.
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      10-09-2020, 12:51 PM   #49
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Quote:
Originally Posted by tsk94 View Post
Shaikh is great guy, and knowledgeable. After all my research and experience with my own setup, I have to disagree with his 'flat-ride' approach to an extent. The caveat being I'm talking strictly track or race application, on a car that sees driving on the street this may not apply to the same extent.
It's not "his" idea...tuning by frequency to product a "flat-ride" is literally how every car mass produced is engineered. Plus or minus other factors to produce the resulting handling characteristics... but the pitch of the vehicle is determined by springs and their frequency (plus some bushings bind etc).
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      10-09-2020, 01:11 PM   #50
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Quote:
Originally Posted by bbnks2 View Post
It's not "his" idea...tuning by frequency to product a "flat-ride" is literally how every car mass produced is engineered. Plus or minus other factors to produce the resulting handling characteristics... but the pitch of the vehicle is determined by springs and their frequency (plus some bushings bind etc).
I never said it's 'his idea', I said his 'approach', which uses flat-ride. But he's one of the first to bring it to the aftermarket on the performance suspension side of things (that has become widely recognized) with his work with flat-ride Miata suspension for AutoX and track/race use.

Manufacturers using flat-ride is almost competently irrelevant to this case we're talking about, that is spring rates for road racing. The 2 have very different goals in mind.

Last edited by tsk94; 12-10-2020 at 01:47 PM..
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      10-09-2020, 01:18 PM   #51
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Quote:
Originally Posted by tsk94 View Post
I never said it's 'his idea', I said his 'approach', which uses flat-ride. But he's one of the first to bring it to the aftermarket on the performance suspension side of things (that has become widely recognized) with his work with flat-ride Miata suspension for AutoX and track/race use.

Manufacturers using flat-ride is almost competently irreverent to this case we're talking about, that is spring rates for road racing. The 2 have very different goals in mind.
Just pointing it out that this isn't black magic. This is literally how every single car manufacturer engineers a car. How every vehicle engineering teaches the math behind the design. Obviously manufacturers are much more advanced in their analysis than basic 2d calculations as things do become dynamic as the chassis goes through its motions.

What published research can you link to about using higher front spring rates (relatively higher)? Have not been able to find much other than standardized testing like side step testing in vehicle dynamic showing that you want a higher rear rate in side step testing for what drivers call "better handling" or "responsiveness." quotes because it's a subjective topic as everyone has their own "feeling" or each setup.
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      10-09-2020, 01:29 PM   #52
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Quote:
Originally Posted by bbnks2 View Post
Just pointing it out that this isn't black magic. This is literally how every single car manufacturer engineers a car. How every vehicle engineering teaches the math behind the design. Obviously manufacturers are much more advanced in their analysis than basic 2d calculations as things do become dynamic as the chassis goes through its motions.

What published research can you link to about using higher front spring rates (relatively higher)? Have not been able to find much other than standardized testing like side step testing in vehicle dynamic showing that you want a higher rear rate in side step testing for what drivers call "better handling" or "responsiveness." quotes because it's a subjective topic as everyone has their own "feeling" or each setup.
I'm a bit confused as to why you bring this up again now. I've both publicly and privately (to yourself) stated that I've changed my opinion on flat-ride being a less optimal approach then the traditional method.

I believe that a flat-ride setup can just as good as a traditional approach - whether it's better or not will constantly be for debate until someone with the same car, with the same suspension, runs both traditional (front biased) and flat-ride setup (with the car being optimized and dialed in for each setup) to compare in an unbiased manner. I feel like a flat-ride approach can be very good, assuming the rest of the car is setup around it accordingly. I also know, from my own experience, that traditional front biased setups can also be very good - as I've experienced them on numerous race cars I've driven up until now.
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      10-09-2020, 01:38 PM   #53
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Quote:
Originally Posted by tsk94 View Post
I'm a bit confused as to why you bring this up again now. I've both publicly and privately (to yourself) stated that I've changed my opinion on flat-ride being a less optimal approach then the traditional method.

I believe that a flat-ride setup can just as good as a traditional approach - whether it's better or not will constantly be for debate until someone with the same car, with the same suspension, runs both traditional (front biased) and flat-ride setup (with the car being optimized and dialed in for each setup) to compare in an unbiased manner. I feel like a flat-ride approach can be very good, assuming the rest of the car is setup around it accordingly. I also know, from my own experience, that traditional front biased setups can also be very good - as I've experienced them on numerous race cars I've driven up until now.
my mistake. I mis-read the dates on the posts thinking this was new. I just re-read the thread and realized I laid all this out in much more detail.

but again, tuning for "flat-ride" doesn't mean the car has to be "neutral." you can still throw a big bar on the car and make it crazy understeer oriented. But, the car will handle curbs and track imperfections much better without the pitch moment being out of phase f:r. Aftermarket sways don't bind in pitch/dive and so long as end-links are adjusted correctly the springs will be controlling those moments (acceleration/braking/bumps).

Most importantly to note with these threads is that most of these discussions about spring rates on an E82/E9x pop up within the context of understeer behavior and people running big front bars AND massively stiffer front springs like an E46 spring rate setup. Lots of people run 400/600 or 450/700 etc with upgraded front sways. Worked great on an E46 but again to get the same handling car in an E82 you would need to bump the rear rate up to 900+. Then new people come in like above and ask why people are removing their front sways /facepalm. No one ever said to run an E82 without a front sway. I feel partly responsible for this since I recommended it to people who didn't believe their understeer was due to their own setup... Pulled front sway and saw how much better the front end hooked up... only ever recommended it because it takes all of 15 minutes to pull the endlinks and see how the handling changes.

Last edited by bbnks2; 10-09-2020 at 01:43 PM..
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      10-09-2020, 01:48 PM   #54
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Quote:
Originally Posted by bbnks2 View Post
my mistake. I mis-read the dates on the posts thinking this was new. I just re-read the thread and realized I laid all this out in much more detail.

but again, tuning for "flat-ride" doesn't mean the car has to be "neutral." you can still throw a big bar on the car and make it crazy understeer oriented. But, the car will handle curbs and track imperfections much better without the pitch moment being out of phase f:r. Aftermarket sways don't bind in pitch/dive and so long as end-links are adjusted correctly the springs will be controlling those moments (acceleration/braking/bumps).

Most importantly to note with these threads is that most of these discussions about spring rates on an E82/E9x pop up within the context of understeer behavior and people running big front bars AND massively stiffer front springs like an E46 spring rate setup. Lots of people run 400/600 or 450/700 etc with upgraded front sways. Worked great on an E46 but again to get the same handling car in an E82 you would need to bump the rear rate up to 900+. Then new people come in like above and ask why people are removing their front sways /facepalm. No one ever said to run an E82 without a front sway. I feel partly responsible for this since I recommended it to people who didn't believe their understeer was due to their own setup... Pulled front sway and saw how much better the front end hooked up... only ever recommended it because it takes all of 15 minutes to pull the endlinks and see how the handling changes.
No problem.

I understand that a flat-ride car doesn't need to be neutral by association. The same way a front-biased setup doesn't have to be understeer biased. My quite heavily 'front-biased' suspension on my E92 rides curbs better then anything I've ever driven on track - but that could largely be due to the excellent damping a of high-quality race shock.

At the end of the day there's more then 1 way to approach suspension setup for track/race use. There are countless examples of front-biased setups from professional and factory race teams, they make it work and work well. There are also examples (much less, but growing in number) of flat-ride approaches that seems to also work very well and have good results.

Just like there is more then 1 way to drive a car fast, there is more then 1 way to setup a car to be fast.
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      10-09-2020, 06:43 PM   #55
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It's likely your fast damping.

Stiff ARBs actually aren't great on kerbs. It depends on the kerb/bumps. You're basically interlocking the entire axle.

Stiff front springs can also be used to reduce pitch sensitivity and keep geometry change within an optimal window. Obviously, pitch sensitivity is more important on aero dominant cars like true SRO/IMSA GT3 class cars. The data/experience from Strom and their upright development indirectly supports that on this particular car generation though.
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      10-15-2020, 03:16 PM   #56
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I'm still intrigued by the notion of a flat-ride style setup and would someday like to try it myself, specifically on a car that I've used a more traditional (pitch style) setup on as well - such as my M3. However, I'm not sure it's as simple as going to a softer spring rate up front and revalving accordingly with my KW's.

At least from my understanding when speaking to Shaikh, the whole setup is designed and valved accordingly to achieve flat-ride 'properly', including engagement of the bump stops in the front to aid in front roll stiffness at certain points.

I'm thinking of experimenting with it (flat-ride) on my 128i, which will be converted to a track/race car in the coming years. The E82 and E92 platform are very similar, so if the results are positive on the E82 I'm sure it would easily transfer over to the M3 and other platforms for that matter.

Ideally I could convince either YCW or FCM to send me a race setup of their suspension for my M3 so I can directly compare it to my current suspension and provide a good pitch vs. flat-ride comparison - would make an interesting thread . But that's unlikely to happen..

Last edited by tsk94; 10-15-2020 at 03:51 PM..
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      10-15-2020, 05:33 PM   #57
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Quote:
Originally Posted by imported_mega View Post
does anyone make adjustable front swaybars that will go softer than stock?

I have ran with the front disconnected and I liked it but I would prefer to retain some adjustability
I've never seen something like this for a BMW. Even on adjustable bars the softest settings is usually stiffer then stock.

Just weld on a 2nd adjustment hole to a stock sway bar (or multiple). Then you'll have an adjustable sway bar that can go softer then stock
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      10-16-2020, 08:16 AM   #58
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Quote:
Originally Posted by tsk94 View Post
I've never seen something like this for a BMW. Even on adjustable bars the softest settings is usually stiffer then stock.

Just weld on a 2nd adjustment hole to a stock sway bar (or multiple). Then you'll have an adjustable sway bar that can go softer then stock
yeah maybe he should focus on the rear rather than trying to soften the front up. Just not a good approach since front sway isn't exactly beefy to begin with. just the rear bar is basically nonexistent.
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      10-16-2020, 02:04 PM   #59
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Quote:
Originally Posted by bbnks2 View Post
yeah maybe he should focus on the rear rather than trying to soften the front up. Just not a good approach since front sway isn't exactly beefy to begin with. just the rear bar is basically nonexistent.
I can see where he's coming from.

1) Replacing the rear bar is a PITA since the subframe has to be dropped
2) A Stiffer rear bar unloads inside tire and since I don't have the money/time to install a proper limited slip, maximizing grip across the rear tire pair helps to put power down.

As suggested by tsk94, welding on to the end of the bar and adding a hole(s) is a simple way to soften things up without going to the extreme of disconnecting the bar entirely.

Just make sure to check for binding at full bump/droop with steering turned.
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      10-16-2020, 02:51 PM   #60
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I have 6kg/mm front and 12kg/mm rear springs, after this past track weekend I am going to stiffen up the rear with an adjustable bar.

I was very worried about lack of LSD and a stiff rear, turns out my big ass wing makes a huge difference, I cant break the rear loose with new rs4's on the car

oil pressure is a problem though, left hand High G are a big issue..

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      10-17-2020, 07:11 AM   #61
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Thought of making the OEM bar adjustable to exploit loopholes in our local rules. Good idea in theory, not in practice.
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      10-17-2020, 03:33 PM   #62
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Quote:
Originally Posted by gmx View Post
Thought of making the OEM bar adjustable to exploit loopholes in our local rules. Good idea in theory, not in practice.
In what way is not good in practice? Depends on the situation, but if you are looking to soften the roll stiffness and don't want to do so with spring rates, this is a viable option. Especially considering there are 0 options available for aftermarket bars that are adjustable and softer then stock.
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      10-17-2020, 07:22 PM   #63
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I wouldn't chop then reweld onto a roll bar. You could try drill into the tube section and leave it as a tube or take a hammer to it.

Genuine GT4 is your only off-the-shelf option. Read the rules, read the specs. It's adjustable with the same diameter and initial length as the factory car. That's the whole point of GT4...
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      10-17-2020, 07:50 PM   #64
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Quote:
Originally Posted by gmx View Post
I wouldn't chop then reweld onto a roll bar. You could try drill into the tube section and leave it as a tube or take a hammer to it.

Genuine GT4 is your only off-the-shelf option. Read the rules, read the specs. It's adjustable with the same diameter and initial length as the factory car. That's the whole point of GT4...
No chopping needed. Simply fab up a piece and weld onto the original bar. Done this myself on my own race cars and seen it countless times. If done correctly it's as strong (or stronger even) then original while adding adjustments for softer settings.

What rules are you referring to? Most sanctioning bodies don't care what sway bars you're using, whether they are OEM, aftermarket or modified in any way.

Also, the GT4 bars aren't adjustable from my understanding, at least on the E92 M3 GT4 - which is what I assume you're referring to.
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