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      09-21-2020, 10:03 PM   #67
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PSA: If you install these and feel that the ride is too stiff, you probably have the ride height set too low. At first it felt really oversprung to me, then I raised it up about a half an inch, and it was amazing how much better it rode.

Just finished a trip to the racetrack with them. They performed very well in Sport Plus. They also work great with the ground control camber plates. Really happy with the decision.
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      09-22-2020, 02:39 PM   #68
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Quote:
Originally Posted by biofluke View Post
PSA: If you install these and feel that the ride is too stiff, you probably have the ride height set too low. At first it felt really oversprung to me, then I raised it up about a half an inch, and it was amazing how much better it rode.

Just finished a trip to the racetrack with them. They performed very well in Sport Plus. They also work great with the ground control camber plates. Really happy with the decision.
The B16D are partially threaded coil overs. There is no separate height adjustment from preload. So the higher up you set the height, the more compressed the spring becomes.

So you need to choose between spring stiffness and shock travel. I'm sure slamming to the lowest setting doesn't help in any case, but I was somewhere in the middle of the height settings, and the ride was miserable.
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      09-22-2020, 02:48 PM   #69
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Quote:
Originally Posted by ntg44 View Post
The B16D are partially threaded coil overs. There is no separate height adjustment from preload. So the higher up you set the height, the more compressed the spring becomes.
His ride quality likely improved because there's now more shock travel before bump stop engagement.
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      09-22-2020, 03:12 PM   #70
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Originally Posted by FaRKle! View Post
His ride quality likely improved because there's now more shock travel before bump stop engagement.
That's very possible, but I wanted to clarify to potential readers who might read that comment as raising the height decreases spring stiffness, because it most definitely does not on the B16. It in fact does the opposite by increasing spring preload to raise the height.

In reality, I'm sure it's not by much and the kit is tuned to perform best when within recommended height settings.
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      09-22-2020, 04:29 PM   #71
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Spring stiffness does not change with preload. This article does a good job of explaining this.

http://www.superstreetonline.com/how...the%20opposite.
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      09-23-2020, 09:49 PM   #72
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Quote:
Originally Posted by ntg44 View Post
That's very possible, but I wanted to clarify to potential readers who might read that comment as raising the height decreases spring stiffness, because it most definitely does not on the B16. It in fact does the opposite by increasing spring preload to raise the height.

In reality, I'm sure it's not by much and the kit is tuned to perform best when within recommended height settings.
I'm still honestly trying to understand how raising ride height increases spring stiffness. The only way it would do that is if the top of the shock relative to the ground doesn't change in height as you raise the spring perch. Of course, as you raise the perch, the top of the shock and the rest of the car goes up by the same amt that you raise the perch so not sure how preload is increased.

What I think happens when you raise the perch is the shock piston is extended further up along with the height of the top of the upper spring mount. The spring itself is not compressed any further. If it was, the car would not be raised when you move the spring perch up.
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      09-24-2020, 07:48 AM   #73
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Quote:
Originally Posted by AlterZgo View Post
I'm still honestly trying to understand how raising ride height increases spring stiffness. The only way it would do that is if the top of the shock relative to the ground doesn't change in height as you raise the spring perch. Of course, as you raise the perch, the top of the shock and the rest of the car goes up by the same amt that you raise the perch so not sure how preload is increased.

What I think happens when you raise the perch is the shock piston is extended further up along with the height of the top of the upper spring mount. The spring itself is not compressed any further. If it was, the car would not be raised when you move the spring perch up.
Read up on partially vs fully threaded coil overs.

On partially threaded like the B16, you adjust the height by adjusting the preload on the spring. The higher the height setting, the more the spring is compressed. It's really as simple as that.

There's a reason higher end coil overs have independent height adjustment from preload. To not have this issue. The spring has the same preload and thus same initial force no matter which height it is set to.
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      09-24-2020, 11:16 AM   #74
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Quote:
Originally Posted by ntg44 View Post
Read up on partially vs fully threaded coil overs.
I think this FB post sums it up and is consistent with my experience.

This is my understanding. The total shock travel is made up of compression stroke (called "bump" stroke as the shock is compressed when you hit a bump) and rebound or extension stroke (called "droop" which happens when the shock is extended). The total suspension travel is droop+bump stroke.

So, let's assume the car has 4" of total suspension travel when sitting on the ground and ride height is set such that the spring/shock can compress 2.5" before it hits and fully compresses the bump stops and can extend or rebound up 1.5" before it tops out and can no longer extend any further.

When the car is sitting on the ground, assuming 50/50 weight distribution and 3600 lb car, on each corner of the suspension 900 lbs of force is being exerted. This compresses and preloads the spring.

If you raise the spring perch by .5", you are basically pulling the shock piston up by .5", thus raising the car by .5". The distance between the top hat of the suspension and the spring perch does not change when you raise the perch. If this distance decrased, you would be adding preload to the spring. Instead, what happens is the car just goes up by .5" as the spring perch is raised .5". So with this adjustment, the compression stroke available increases from 2.5" to 3" but the rebound stroke available (how much the suspension can extend up before topping out) decreases from 1.5" to 1".

You can see how much potential rebound stroke is available by observing what happens with the shock when you jack up the car. As you raise the body of the car, initially, the tire continues to sit on the floor as the suspension is being unweighted and extended. The bottom of the shock that's bolted to the hub of the rim/tire is static as the top of the shock is raised thereby pulling and extending the shock piston. Once you raise the body of the car several inches and the shock piston cannot extend any further (shock now topped out) the tire lifts off the ground. The amount that you were able to raise the car before the tire comes off the ground represents how much rebound or droop travel your shock can move before it is completely topped out.

So, when you raise a car by moving the spring perch up by .5" in a single adjustable coilover, you are reducing the rebound stroke of the car by .5" (reduces upward movement stroke of the suspension from 1.5" to 1") while adding .5" bump stroke (the amount the suspension can compress before bottoming out increases from 2.5" to 3").

The explanation in the link above is consistent with my experience with the several single adjustable coilover set ups I've had in multiple cars. Whenever I raised the spring perch on these cars, the ride height goes up and the ride quality always noticeably improved because I was not adding any significant amt of preload to the spring and was, in fact increasing suspension travel for the compression stroke. I've had the exact same experience with my Blistein coilovers on my F80. It is presently set to the highest setting in front and fairly high in the rear and the car rides noticeably better than when it was set about 1/2 way down.
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      09-24-2020, 03:07 PM   #75
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Quote:
Originally Posted by ntg44 View Post
Read up on partially vs fully threaded coil overs.

On partially threaded like the B16, you adjust the height by adjusting the preload on the spring. The higher the height setting, the more the spring is compressed. It's really as simple as that.
^This is incorrect for this platform.

Quote:
Originally Posted by AlterZgo View Post
What I think happens when you raise the perch is the shock piston is extended further up along with the height of the top of the upper spring mount. The spring itself is not compressed any further. If it was, the car would not be raised when you move the spring perch up.
^This is correct.

The only time moving the spring perch increases preload is if the car being set on the ground wouldn't compress the spring from where it is in droop.
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      09-25-2020, 04:53 PM   #76
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Quote:
Originally Posted by FaRKle! View Post
^This is incorrect for this platform.


^This is correct.

The only time moving the spring perch increases preload is if the car being set on the ground wouldn't compress the spring from where it is in droop.
+1
KW goes into detail regarding preload and ride height here as well, just scroll down a bit.
http://blog-int.kwautomotive.net/in-...in-the-bmw-m4/
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      10-05-2020, 02:29 PM   #77
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Quote:
Originally Posted by SE7EN335 View Post
Yeah I'm waiting to snag them up on upcoming Black Friday sale discount this year. Hopefully its as big of a discount as compared with last year's. Deciding between either the B16 Damptronic or the KW DDC so its a tough choice, and considering whether the additional cost of the KW DDC is actually worth it
Can you tell me where you will find them discounted?
I'm pretty sure im going with these after the review but would want them discounted.

Let me know either PM or here.
Thanks
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      10-05-2020, 02:52 PM   #78
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Quote:
Originally Posted by ByeFelicia View Post
Quote:
Originally Posted by SE7EN335 View Post
Yeah I'm waiting to snag them up on upcoming Black Friday sale discount this year. Hopefully its as big of a discount as compared with last year's. Deciding between either the B16 Damptronic or the KW DDC so its a tough choice, and considering whether the additional cost of the KW DDC is actually worth it
Can you tell me where you will find them discounted?
I'm pretty sure im going with these after the review but would want them discounted.

Let me know either PM or here.
Thanks
I bought them discounted and I think I paid $2,890 or so... take it for what it's worth since every Black Friday has different promotions haha... I've been tracking Black Friday pricing and I've noticed price increases year after year since I still have old receipts on my past Black Friday shopping from years ago.
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      10-05-2020, 04:24 PM   #79
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Quote:
Originally Posted by hellokitty View Post
I bought them discounted and I think I paid $2,890 or so... take it for what it's worth since every Black Friday has different promotions haha... I've been tracking Black Friday pricing and I've noticed price increases year after year since I still have old receipts on my past Black Friday shopping from years ago.
Right, im curious what retail link though? Is this Bilstein selling them directly with a black friday code? or a third party like IND/Turner etc?

Also since this is referenced to you the OP, I dont have EDC on my car but I have to imagine the non EDC version of the coils should ride/feel the same as the Damptronic version?
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      10-05-2020, 04:26 PM   #80
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Quote:
Originally Posted by ByeFelicia View Post
Quote:
Originally Posted by hellokitty View Post
I bought them discounted and I think I paid $2,890 or so... take it for what it's worth since every Black Friday has different promotions haha... I've been tracking Black Friday pricing and I've noticed price increases year after year since I still have old receipts on my past Black Friday shopping from years ago.
Right, im curious what retail link though? Is this Bilstein selling them directly with a black friday code? or a third party like IND/Turner etc?

Also since this is referenced to you the OP, I dont have EDC on my car but I have to imagine the non EDC version of the coils should ride/feel the same as the Damptronic version?
Yes, they will ride the same. The only difference is on the fly adjustability.

IND or extreme power house are good sources for Black Friday sales. I would follow all the vendors on Instagram so you know what codes to apply for Black Friday.
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      10-05-2020, 04:35 PM   #81
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Quote:
Originally Posted by ByeFelicia View Post
Right, im curious what retail link though? Is this Bilstein selling them directly with a black friday code? or a third party like IND/Turner etc?

Also since this is referenced to you the OP, I dont have EDC on my car but I have to imagine the non EDC version of the coils should ride/feel the same as the Damptronic version?
Try https://www.demon-tweeks.com/au/brand/bilstein/

or Evolve UK
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      10-26-2020, 09:24 PM   #82
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Looking for a new suspension setup for my F80 zcp and these are the top of my list. Waiting for Black Friday as well on a deal.
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      10-28-2020, 05:01 AM   #83
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Originally Posted by SMC23 View Post
Looking for a new suspension setup for my F80 zcp and these are the top of my list. Waiting for Black Friday as well on a deal.
me too
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      10-29-2020, 12:18 PM   #84
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me too
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      11-18-2020, 09:25 AM   #85
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Quote:
Originally Posted by horsepower_and_hounds View Post
Quote:
Originally Posted by TheMaster1971NL View Post
me too
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Hey guys, just placed an order through Turner Motorsport for a good deal. Since these are not advertised as on-sale on their site, I would recommend reaching out to the following contact at Turner if you're serious about purchasing.

Ian Shea
ishea@turnermotorsport.com

Looking forward to getting them on!
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      11-19-2020, 12:08 PM   #86
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Quote:
Originally Posted by f80tanz View Post
Hey guys, just placed an order through Turner Motorsport for a good deal. Since these are not advertised as on-sale on their site, I would recommend reaching out to the following contact at Turner if you're serious about purchasing.

Ian Shea
ishea@turnermotorsport.com

Looking forward to getting them on!
Your supposed to post what the deal was.... or it does not count
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      11-25-2020, 01:00 PM   #87
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Have been reading all the posts with great interest and would like to pull trigger to take advantage of BF sales, if any occur. My only concern is that I live in Calif. and roads are not good. I have an '18 F80 zcp with EDC and 20" wheels and really don't want to ruin the ride for DD, it is already pretty firm on the 20's. I like idea of leveraging EDC so if/when track can go all out and use comfort on poor roads. I don't mind firm, but jarring when hitting poor sections of road not so much. I guess just looking for final feedback that I wont be ruining the ride. Would like lower stance and improved handing then I'm all in.
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      11-25-2020, 01:57 PM   #88
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Quote:
Originally Posted by GregSM3 View Post
Have been reading all the posts with great interest and would like to pull trigger to take advantage of BF sales, if any occur. My only concern is that I live in Calif. and roads are not good. I have an '18 F80 zcp with EDC and 20" wheels and really don't want to ruin the ride for DD, it is already pretty firm on the 20's. I like idea of leveraging EDC so if/when track can go all out and use comfort on poor roads. I don't mind firm, but jarring when hitting poor sections of road not so much. I guess just looking for final feedback that I wont be ruining the ride. Would like lower stance and improved handing then I'm all in.
You may want the KW DDC then if you want soft.
I live in CA as well... I don’t have too many “jarring” impacts and I run 20’s. Firmer, oh yes, but I’m also lower than should be at the moment.

Others have reported better comfort with the KW’s.
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