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      06-13-2020, 06:15 PM   #23
leadfoot12
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Thanks for all the feedback everyone, it is appreciated.

One more question, for those that have the R&T installed, how have they held up? Anyone had to do a rebuild yet? I see Ohlins recommends "maintenance" every 60k miles.
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      06-13-2020, 10:44 PM   #24
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Anyone have Ohlins in the SF Bay Area I can try before buying? You can try my oem m sport suspension
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      06-14-2020, 12:19 AM   #25
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Originally Posted by nadefade View Post
Anyone have Ohlins in the SF Bay Area I can try before buying? You can try my oem m sport suspension
kreuz has them on his 435i. He participated in the last suspension demo day where we got a bunch of enthusiasts together to try different set ups back to back. I'm interested in putting together another one once social gathering guidelines ease up a bit since we're limited to gatherings up to 12 people. Then again, we can always call it a "protest" and have up to 100 legally... lol
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      06-14-2020, 12:40 AM   #26
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Quote:
Originally Posted by FaRKle! View Post
Quote:
Originally Posted by nadefade View Post
Anyone have Ohlins in the SF Bay Area I can try before buying? You can try my oem m sport suspension
kreuz has them on his 435i. He participated in the last suspension demo day where we got a bunch of enthusiasts together to try different set ups back to back. I'm interested in putting together another one once social gathering guidelines ease up a bit since we're limited to gatherings up to 12 people. Then again, we can always call it a "protest" and have up to 100 legally... lol
LOL count me in for the next meet/protest
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      06-14-2020, 02:11 PM   #27
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Quote:
Originally Posted by leadfoot12 View Post
Thanks for all the feedback everyone, it is appreciated.

One more question, for those that have the R&T installed, how have they held up? Anyone had to do a rebuild yet? I see Ohlins recommends "maintenance" every 60k miles.
I had my R&T serviced after 25K miles.

This was to try and cure a persistent knocking from the front suspension which has only become a problem since fitting Milway top mounts and the Ohlins R&T.

The Milway plates have since been remanufactured to take an uprated monoball although the original monoball was found to be zero defect - it was still as tight as the day it was fitted. [EDIT - specifically, I had the Millway camber plates on my car modified to utilise a substantially upgraded monoball - however, when the components were switched and we examining the Millway monoball at 7K miles there was no evidence of any wear]

Attention then turned to the R&T dampers. These were stripped, the nylon guide bushes were checked (and confirmed to be the previous style - not the newer design which have caused noise problems), and rebuilt. There was some discolouration on the outer surfaces of the inverted monotubes, most likely due to heat from track days, and this was skimmed off using a lathe. Apart from that the dampers were given a clear health check.

Unfortunately the noise persists. I haven't been able to rule-out valve knock as the source of the noise. The only way would be to have my BMW Adaptive dampers refitted, with all other suspension components remaining the same, as a back-to-back test.

Suspension noise has been reported by several people who have installed R&T, but to my knowledge no-one has found the 100% reliable source and a 100% guranteed fix.

Installing Milway 'street' plates would almost certainly cure the problem, by isolating the sound from the chassis. My hesitancy comes from this solution relying on a poly washer, rather than a monoball, to allow articulation of the damper piston rod relative to the suspension turret and that's something which I currently prefer to avoid. That's just my preference though. A friend has the street version fitted to his M4 (running AC Schnitzer RS, which is apparently a re-valved version of KW V3) and he hasn't mentioned anything about knocking.

Maybe that means the street plates are isolating NVH, or maybe the KW V3 dampers are quieter. Who knows.
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Last edited by Watsey; 06-16-2020 at 02:54 AM.. Reason: clarification - see [EDIT...]
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      06-15-2020, 11:09 AM   #28
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Originally Posted by FaRKle! View Post
Another method to reduce oversteer could've been to remove the H&R rear bar and go back to the OE one instead of increasing the front spring rate.

That's the method I used on my vehicle when I had oversteer issues. When you get to as high rear spring rates as we have (I'm running 900lbs/in, 16kg/mm too), you really don't need much rear bar.
True, but the car was well balanced with the H&R sway bars before adding the Ohlins coils... and the corner weight analysis indicated that the front spring rates were low. So I felt it was better to simply correct the front spring rate, rather than to try to offset the mismatch with a weaker rear sway bar. This would have been a step back in motion control - not to mention changing rear sway bars is a huge job. Adjusting sway bars stiffness is generally the last thing to do once you've gotten everything else right; I wouldn't make sway bar adjustments to try to fix incorrect spring rates.
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      06-15-2020, 11:12 AM   #29
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Originally Posted by Watsey View Post
I had my R&T serviced after 25K miles.

This was to try and cure a persistent knocking from the front suspension which has only become a problem since fitting Milway top mounts and the Ohlins R&T.

The Milway plates have since been remanufactured to take an uprated monoball although the original monoball was found to be zero defect - it was still as tight as the day it was fitted.

Attention then turned to the R&T dampers. These were stripped, the nylon guide bushes were checked (and confirmed to be the previous style - not the newer design which have caused noise problems), and rebuilt. There was some discolouration on the outer surfaces of the inverted monotubes, most likely due to heat from track days, and this was skimmed off using a lathe. Apart from that the dampers were given a clear health check.

Unfortunately the noise persists. I haven't been able to rule-out valve knock as the source of the noise. The only way would be to have my BMW Adaptive dampers refitted, with all other suspension components remaining the same, as a back-to-back test.

Suspension noise has been reported by several people who have installed R&T, but to my knowledge no-one has found the 100% reliable source and a 100% guranteed fix.

Installing Milway 'street' plates would almost certainly cure the problem, by isolating the sound from the chassis. My hesitancy comes from this solution relying on a poly washer, rather than a monoball, to allow articulation of the damper piston rod relative to the suspension turret and that's something which I currently prefer to avoid. That's just my preference though. A friend has the street version fitted to his M4 (running AC Schnitzer RS, which is apparently a re-valved version of KW V3) and he hasn't mentioned anything about knocking.

Maybe that means the street plates are isolating NVH, or maybe the KW V3 dampers are quieter. Who knows.
I'd bet that the noise is coming from the camber plates.... it's rare to find a set that's actually quiet.
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      06-15-2020, 11:55 AM   #30
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Originally Posted by DVC View Post
True, but the car was well balanced with the H&R sway bars before adding the Ohlins coils...
IMO what it was before with a different setup is irrelevant to afterwards with Ohlins. You had a completely different F:R ride frequencies, ratio, and the amount of roll couple the bars were contributing.

Quote:
Originally Posted by DVC View Post
and the corner weight analysis indicated that the front spring rates were low. So I felt it was better to simply correct the front spring rate, rather than to try to offset the mismatch with a weaker rear sway bar. This would have been a step back in motion control - not to mention changing rear sway bars is a huge job.
How much would you have needed to raise the front with the original Ohlin's springs, and what front/rear height delta did that produce? Sway bars (generally speaking) reduce grip on the axle they're applied to, so I prefer adding grip to the axle that needs it rather than taking it away from the one with more.
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      06-15-2020, 03:10 PM   #31
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Originally Posted by FaRKle! View Post
IMO what it was before with a different setup is irrelevant to afterwards with Ohlins. You had a completely different F:R ride frequencies, ratio, and the amount of roll couple the bars were contributing.
I disagree - everything on the car was the same, except for the dampers/springs. No need to overthink it; the comparatively light front spring weight threw things out of balance. Both the Ohlins rep and the Swift springs engineer agreed with me on this.


Quote:
Originally Posted by FaRKle! View Post
How much would you have needed to raise the front with the original Ohlin's springs, and what front/rear height delta did that produce? Sway bars (generally speaking) reduce grip on the axle they're applied to, so I prefer adding grip to the axle that needs it rather than taking it away from the one with more.
Ideal front spring rate was 8kg, so +2kg from the Ohlins kit; no change in ride height.
Sway bars control body motion; the reduced grip with more bar is a function of reducing the loading on the outside tire. Retrofitting a VERY weak OE rear sway bar to pair with a strong aftermarket front sway bar in order to compensate for Ohlins specing the front springs too light (based on development for a 320d) would be like cranking down on your shoe laces in one show to hold your foot in place instead of starting with the correct size pair of shoes to begin with. Sway bar strength is the LAST thing to dial in, in order to fine tune handling; it's not a replacement for proper spring rates.
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      06-15-2020, 04:24 PM   #32
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Originally Posted by DVC View Post
I'd bet that the noise is coming from the camber plates.... it's rare to find a set that's actually quiet.
The camber plates will be transmitting the noise, but they're not causing it.

The monoballs are tight, i.e. absolutely no wear, the camber plates are secure in the suspension turrets and the sliding plate is also securely fixed. There's no slop in the components which could be causing the knocking - it's definitely coming from somewhere else.
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      06-15-2020, 06:12 PM   #33
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Quote:
Originally Posted by DVC View Post
Sway bars control body motion; the reduced grip with more bar is a function of reducing the loading on the outside tire. Retrofitting a VERY weak OE rear sway bar to pair with a strong aftermarket front sway bar in order to compensate for Ohlins specing the front springs too light (based on development for a 320d) would be like cranking down on your shoe laces in one show to hold your foot in place instead of starting with the correct size pair of shoes to begin with. Sway bar strength is the LAST thing to dial in, in order to fine tune handling; it's not a replacement for proper spring rates.
I understand your aftermarket sway bars were already installed, but if sway bars are the LAST thing to dial in, why would you start with anything other than OE and adjust the spring rates to match? Doesn't it sound like the spring rates would have been on point with the OE sways?
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      06-15-2020, 08:54 PM   #34
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Quote:
Originally Posted by nadefade View Post
I understand your aftermarket sway bars were already installed, but if sway bars are the LAST thing to dial in, why would you start with anything other than OE and adjust the spring rates to match? Doesn't it sound like the spring rates would have been on point with the OE sways?
The spring rates would not have been on point with OE sways either. The corner weight analysis has nothing to do with sway bars, so the front springs were too light, period.

I think you're confused by what I mean by 'adjusting' sway bars... I mean making fine adjustments to bars that are adjustable, not retrofitting weak OE street bars back onto the car.
And I definitely wouldn't recommend a strong front bar like the H&R, with a spaghetti-thin OE rear sway bar that was designed for a plush ride on the street. The improved motion control that my H&R sway bars provide is better suited to a firmer, upgraded suspension, so I would never consider spending 10+ hours removing upgraded sway bars, and retrofitting OEM weak sway bars based on a handling quirk that was introduced by a kit with too light of a front spring.

I feel like I'm repeating myself here. The OP asked for advise on front spring rates from those with experience with the Ohlins kit... so I jumped in to share what I've learned. The Ohlins are a fantastic coil over, with exceptional flexibility for varied spring rates within the valving. For the money, it's a really outstanding kit.... it just needs a stiffer front spring for a 335
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      06-15-2020, 10:41 PM   #35
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How did the corner weight analysis point to higher front spring rate? My understanding (which may well be incomplete) is that corner weighting is purely a static measurement and thus is not affected by spring rates. Ride height changes will affect corner weights, but changing springs while maintaining ride height will not affect corner weights (ignoring change in mass because of the different springs).

Of course, accurate corner weights are very helpful in calculating ride frequencies. I suspect that even for a 335 the ride frequencies would point towards keeping the standard front Ohlins spring rate to maintain a good delta between front and rear frequencies (unless you are looking to change both front and rear springs). It's an important point to understand for the OP looking at the Ohlins coilovers!
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      06-16-2020, 12:49 AM   #36
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Quote:
Originally Posted by DVC View Post
Ideal front spring rate was 8kg, so +2kg from the Ohlins kit; no change in ride height.
I asked about the height, not spring rate because you said the below:
Quote:
Originally Posted by DVC
the corner weight analysis indicated that the front spring rates were low.
The only way corner taking corner weights would say you have too soft of a spring rate is if your front ride height was much different compared to the rear in order to achieve corner balance.


Quote:
Originally Posted by nadefade View Post
I understand your aftermarket sway bars were already installed, but if sway bars are the LAST thing to dial in, why would you start with anything other than OE and adjust the spring rates to match? Doesn't it sound like the spring rates would have been on point with the OE sways?
I have to agree with you. The way I was reading it is the sway bars were changed first, and then the springs altered because of how the below handling was after the H&R sways + Ohlins.
Quote:
Originally Posted by DVC View Post
After getting the kit installed, I noticed on the drive home from the shop that the car was prone to oversteer.

Quote:
Originally Posted by DVC View Post
The Ohlins are a fantastic coil over, with exceptional flexibility for varied spring rates within the valving. For the money, it's a really outstanding kit.
This, we agree.
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Last edited by FaRKle!; 06-16-2020 at 08:52 AM..
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      06-16-2020, 10:26 AM   #37
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I said 'corner weight analysis', but what I really meant was the motion ratio calculations that the Swift spring engineer performed, using corner weights, force ratios, angle correction factors, etc. The result was that an 8kg front spring was the right match for a 16kg rear spring on an F30 335.

Sorry, but I'm done with this discussion guys.... I've tried to offer my input to help, but this thread has taken a strange turn. If you guys all have your minds made up to stick with 6kg springs in front on this kit, then so be it.
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      06-16-2020, 11:52 PM   #38
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Hi Guys, I'm in the midst of getting myself Ohlins R&T to replace the stock adaptive M. Just curious is anyone running on 20"s wheels on this coilovers? I'm on 405m with 235/35 & 265/30, was wondering will the ride be jarring?
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      06-17-2020, 05:18 AM   #39
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Hi Guys, I'm in the midst of getting myself Ohlins R&T to replace the stock adaptive M. Just curious is anyone running on 20"s wheels on this coilovers? I'm on 405m with 235/35 & 265/30, was wondering will the ride be jarring?
A lot will depend on the quality of the roads which you drive on.

Whatever you do, and hopefully you have already, get rid of the run flat tyres.

The UK agents for AC Schnitzer advise 20s only for looks; 19s for ride and handling.

My car is running 19s with Michelin Pilot Sport 4S XL (stiffer sidewalls) and the ride is firm but fine.
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      06-17-2020, 10:22 PM   #40
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Originally Posted by Watsey View Post
A lot will depend on the quality of the roads which you drive on.

Whatever you do, and hopefully you have already, get rid of the run flat tyres.

The UK agents for AC Schnitzer advise 20s only for looks; 19s for ride and handling.

My car is running 19s with Michelin Pilot Sport 4S XL (stiffer sidewalls) and the ride is firm but fine.
The ride on 20s is actually pretty ok on the adaptive M with H&R springs. But it is bouncy and loose on the sport mode. Which is the reason i'm looking for a coilover setup. The 405m are pretty light, compared to the normal 19s. I have ditch the run flat and I'm on PS4S as well, was actually thinking to downgrade to 18" square setup when the ohlins are on. But in my region, PS4S does not come in 18s, only 19s & above. So now still looking for options on the wheel, will keep it at 20s now and see how it goes.

Last edited by Freakystein; 06-18-2020 at 02:28 AM..
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      06-19-2020, 12:21 PM   #41
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Can anyone confirm the lowering range? I emailed Ohlins directly and got the following reply: "The lowering is at the front 5-25mm and the rear 0-30mm [as compared to the normal 3 model]".

However, the front mounting instructions state: "With both the preload and height adjustments in their standard positions, the vehicle is lowered approximately 20mm when compared to the original suspension...The adjustment range is the standard position -5/+15mm."

Wouldn't this put the front range lowering range at 15-35mm against standard suspension?
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      06-19-2020, 07:46 PM   #42
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I wish I could fit these to xdrive.
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      07-06-2020, 05:11 AM   #43
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Hi guys, prior to the installation of my Ohlins on the F30, is there any hardware i need that i need to change since i'll be change from the EDC to coilovers?
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      07-06-2020, 11:45 AM   #44
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Hi guys, prior to the installation of my Ohlins on the F30, is there any hardware i need that i need to change since i'll be change from the EDC to coilovers?
You'll need another left (US Driver's Side) end link. EDC RWD cars have different L/R end links, and passive setups use the same left end link on both sides.
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