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Old 04-06-2020, 10:12 AM   #29
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I've not read one good thing about the Bilstein single adjustable shaft. They are not very consistent. If anything, you should be able to adapt a better 14mm adjustable shaft and bleed mechanism for less money. (taiwan) Or if its the same diameter OD shaft and stud mount for the pistons (8 or 12mm) on your megans, you can transplant. The guy that built your shocks can probably do this one hand tied behind his back.

They are 'shit' is what I've heard.
The adjuster got a lot better with the switch from PSS9 to PSS10. It's not perfect, but it's not terrible.

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Old 04-06-2020, 10:26 AM   #30
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Here's someone who stuffed a bilstein piston into his BC shock. Problem with his build tho, he did not degass the oil nor did he give enough consideration to the dividing piston position or gas pressure. He used compressed air to charge his shocks not nitrogen gas. That aside, the response of the adjustment is similar but the extra number of detent clicks give you a bit more fine tuning flexibility.

Sorry about the link beforehand, that forum doesnt work quite as nicely.

Edit: effective change of damping pressure from -0 to -20, from -21 o -30 click, little to no change. Based on this dyno compared to the PSS10 linked previously with only effective change in damping pressure at +9(stiffest) to +5 click, so you only have 4 settings that has a notable change in pressures, whereas with te BC adjustments you have 20 clicks to work with out of 30.

Also, the damping profile digressive/digressive compared to the COB enabled PSS10 with a digressive/linear valving. If the Pss10 had as much total damping pressure, the difference between the setting "clicks" will be even larger on he PSS10



Original damper response before revalving for reference:

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Old 04-06-2020, 10:30 AM   #31
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That was my main concern before buying the B16s from you guys. But after driving them that concern was almost entirely eliminated. What about the progressive rear springs of the B16s on an 86 (specifically) makes them not ideal for someone? I have some thoughts of my own, but would especially like to hear your detailed opinion.
TIA, Andrew.
Some of it has been mentioned already, but progressive springs are inherently a compromise. That compromise is worthwhile for some people, and less ideal for others. The change in response and that little bit of extra chassis movement with the progressive spring may not be a big deal. But with stickier tires and a more focused car, it might not be what you want.

Suspension systems for a road car are all about compromise. The more specialized the car gets (for auto-x, the track, or sweet ass rally jumps)...the fewer compromises you want to make. Just one specific part of that in how it relates to a progressive spring would be shock valving. How do you spec rebound damping? Do you set up your valving around the stiffer spring rate or the softer rate? What will the effect be during body roll motions, hard braking, or big bumps?

If you're using less sticky tires and you don't need stiffer spring rates, you can be conservative and it'll be good. But that changes as the car gets more focused.

Hope that helps. EDIT: Again, not saying that progressive spring = bad. Just that it's better in some applications, and not as good as the car gets more track focused (or at least more complicated).

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Old 04-06-2020, 11:53 AM   #32
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Thanks, Andrew. My car is definitely a compromise. I go skiing with it (Colorado) 20+ days annually, take it on 2,000 mile road trips, and compete with it. While I have driven coilovers on the track with stiffer, linear-rate springs, I haven't found them to really be any faster. Granted, I'm not on R7s, A7s, R1s, or R1Ses, either. Normally I'm on SX2s or RC1s. Maybe a better driver would be able to appreciate linear-rate springs in the rear more than me, but given the rest of the hardware package I'm working with, I doubt it would make much of a difference. I believe the spring ratios between front and rear have a WAY bigger impact on lap times. WAY bigger. Getting the car to rotate like you want matters a lot. There's no way I'd know the rears aren't linear if someone didn't tell me. And I don't think my car is unpredictable in the slightest. Quite the opposite, in fact.
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Old 04-06-2020, 06:23 PM   #33
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Sometimes, I want to move to Colorado. Denver's been exploding the past couple years. I wanna snowboard 20 days a year too lol
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Old 04-04-2021, 05:35 PM   #34
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Bilstein adjuster is constrained to the shaft since it adjusts a bleed valve on the piston. They couldn't move it to the bottom without building an inverted damper body for the rear adding weight and cost. KW compression adjuster controls the valve on the damper body that meters fluid to the external fluid reservoir on the twin tube damper so it's always opposite the damper shaft and with a non-inverted front strut design means it's consistently on the bottom of their dampers.

Here's some info on the KW's
https://robrobinette.com/S2000KWV3.htm
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Old 04-05-2021, 01:26 AM   #35
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thanks for the info Strat61caster, would you say its only possible on a mono tube to have it on the lower part if its inverted , but if its twin tube its likely? I kind of got the impression from Bilstein that they don't make many like the 86 design anymore at the rear.

Just a quick question - do people set the rear harder than the front on 1 way coilovers generally on the 86 based on its weight balance?

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Old 04-05-2021, 06:00 AM   #36
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I’m curious if anyone here has tried these B16 or B14 converted with linear springs...it should be relatively easy using Kw hardware like main springs, helpers and upper mounts (v3 or Clubsport if using Kw camber plates)...does anyone know how much spring rate these Bilsteins could tolerate without revalving? Maybe up to 6 or 7kg?
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Old 04-05-2021, 04:18 PM   #37
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Vorshlag has done this, and provides it as a service. I have no first-hand experience. If I were to start from scratch on suspension, this is something I would seriously consider.
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Old 04-05-2021, 04:27 PM   #38
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thanks for the info Strat61caster, would you say its only possible on a mono tube to have it on the lower part if its inverted , but if its twin tube its likely? I kind of got the impression from Bilstein that they don't make many like the 86 design anymore at the rear.

Just a quick question - do people set the rear harder than the front on 1 way coilovers generally on the 86 based on its weight balance?
86 KW twin tubes in the rear are non-inverted just like the Bilsteins, on their single adjustable mechanism or rebound only mechanism on the shaft it's inside the car just like the Bilsteins, it's only the double adjustable that puts compression on the damper body.

As far as I'm aware nobody makes an inverted damper for the rear of the 86, and that's true for most double wishbone/multi-link suspension designs.

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I’m curious if anyone here has tried these B16 or B14 converted with linear springs...it should be relatively easy using Kw hardware like main springs, helpers and upper mounts (v3 or Clubsport if using Kw camber plates)...does anyone know how much spring rate these Bilsteins could tolerate without revalving? Maybe up to 6 or 7kg?
Yes. B14/B16 kit comes with front springs that level out to 4.5kg/mm and rears at 7.0kg/mm, but I've heard +/- 100# (2k) springs can be acceptable, less ideal but sometimes the need for spring rate dominates. I wouldn't hesitate to go up to 7k front and 8k rear and you could probably push a little beyond that, worst case the damping can't keep up and the ride suffers.

Racecomp has done it too iirc, there's a few posts floating around here. I wouldn't mess around with the KW camber plates, I had a bad failure on another platform with their design, if you can import Raceseng camber plates affordably that would be ideal imho.
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Old 04-05-2021, 05:46 PM   #39
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86 KW twin tubes in the rear are non-inverted just like the Bilsteins, on their single adjustable mechanism or rebound only mechanism on the shaft it's inside the car just like the Bilsteins, it's only the double adjustable that puts compression on the damper body.

As far as I'm aware nobody makes an inverted damper for the rear of the 86, and that's true for most double wishbone/multi-link suspension designs.



Yes. B14/B16 kit comes with front springs that level out to 4.5kg/mm and rears at 7.0kg/mm, but I've heard +/- 100# (2k) springs can be acceptable, less ideal but sometimes the need for spring rate dominates. I wouldn't hesitate to go up to 7k front and 8k rear and you could probably push a little beyond that, worst case the damping can't keep up and the ride suffers.

Racecomp has done it too iirc, there's a few posts floating around here. I wouldn't mess around with the KW camber plates, I had a bad failure on another platform with their design, if you can import Raceseng camber plates affordably that would be ideal imho.
It would be interesting, maybe a 7k squared or a 6k 7k, problem is to guess the right spring length to keep a decent height range as these seems to be a bit travel limited like every monotube basically....any tips?
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Old 04-05-2021, 05:57 PM   #40
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No need to guess. Talk to Vorshlag.
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Old 04-05-2021, 06:39 PM   #41
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It would be interesting, maybe a 7k squared or a 6k 7k, problem is to guess the right spring length to keep a decent height range as these seems to be a bit travel limited like every monotube basically....any tips?
I had 325 lb/in 8" tall springs and 425 lb/in 7" tall springs that worked ok for my non-standard setup, I would guess 175mm +/-25mm tall would work for rates <8k.

Since you can only adjust the spring perch, travel will be dictated by where you set the height of the car and your spring rate, it's an odd physics problem to think about but if you are ok with the car sitting up high you should be fine. Set the springs to zero preload (just captured by the spring perch and top hat, slightly loose but no up+down movement) and adjust from there in my opinion.

Calling or emailing vorshlag would be a good idea, they have more experience then I do tuning this system but being in italy I understand that may be difficult.
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