Eibach/Koni vs. Bilstein PSS10 for a street setup

[Tbonem3]

B4, not B6. B6 are sportier monotubes, stiffer, less comfortable.

So for comfort and stock replacement, it's Bilstein B4 and Sachs. For similar comfort with a bit more sportiness (claimed, I don't really think so, maybe a little slower rebound to pair with lowering springs' slightly higher sprint rate) you can get Koni. Bilstein B6 ARE more stout and performance orientated than the aforementioned, but less comfortable (stiffer/harsher) and can be well paired with stock or lowering springs that don't go too low like dinan/eibach. Then, if you want to go a little lower with B6, though it's a big cost, you can put in camber plates, but that will also introduce more NVH too.

[bullet0770]

Are you using the stock springs? I would get Bilstein B4 over Konis. I hate Konis. If sport springs like Eibach, I'd get B6s. If you just want Konis for some reason, I'd run them full soft with stock springs. if Eibachs/Dinans, I'd go very little off full "soft" like a 1/4 turn yes. Then after like 20k miles, probably give them another 1/4 turn and so forth.

I am currently on stock suspension. I am not set on KONI, I was just getting it from your last post. So, B6/Eibach would be equal comfort wise with my worn out shocks? I know performance would be great (without any bump modifications).

Just introduction: I may look newbie here on this forum but I bought the car in 2010 and was active member on m3forum before it vanished 🤦🏻♂️.

Thanks!

[Tbonem3]

H&R fronts are bad because they drop the car way too much (1.2"), but don't increase the spring rate enough to compensate so you're on the bumps constantly, crashing around. I like the H&R rears, however. Only a -.06" drop which is appropriate for this car with already limited travel, and maintains a nice rake which I like, visually. Too bad they didn't just do like a .75" drop up front. Or increase the rate which you could then match rebound to by adjusting koni further.

Adjusting your Konis to full soft up front would be good (unless they have high mileage maybe) because A) they don't need any more rebound than konis provide anyway, but B) that will allow them to return to full travel as quickly as possible to help (slightly) not hit the bumpstop so quickly for the next road bump.

[simon_c]

I have Koni yellows with H&R sport springs and definitely feel like it's a bit harsh. Seems to hit bumps stops all the time. I forgot what setting I have them on but I may adjust them down to full soft. Handles really well though and it's perfect drop height for me. I think I'm just getting old now cause I prefer driving my F15 X5 now cause it's just so damn comfortable for every day driving.

[Tbonem3]

Are you using the stock springs? I would get Bilstein B4 over Konis. I hate Konis. If sport springs like Eibach, I'd get B6s. If you just want Konis for some reason, I'd run them full soft with stock springs. if Eibachs/Dinans, I'd go very little off full "soft" like a 1/4 turn yes. Then after like 20k miles, probably give them another 1/4 turn and so forth.

[bullet0770]

You're welcome, but in my opinion, there's little need for the special tck konis that are top adjustable unless you're going to be testing different springs. The factory springs or common lowering springs don't need any more rebound than the lowest setting (since konis are already "sportier" than stock sachs) esp if your car is a little heavier than average, which lowers effective spring rate thus needing even less rebound.

Maybe people have done a quarter turn or something, but I don't see how you'd need much at all unless you're putting in linear spings like GC kit something like 600lb.

Member Cobra touched on this as well, with actualy shock dyno data:

"I tested my Koni Sport on a dyno and was amazed by the rebound range. With stock or stock-ish springs, you pretty much want full soft. Maybe a TOUCH more in back (like 1/2-3/4 as Tbone mentioned) to balance the handling."

Thanks for your reply. So, you are saying buy normal KONI set with DINAN springs and put on the car? leave the TCK ?

When you say touch more in the rear, you mean 1/2-3/4 turn tight?

[SQ13]

TMS includes a 1/2" spacer that would go beween damper shaft's shoulder and bottom of camber plate/top perch.

Yes, you can shim things. Either like I said above or you could add a 60mm ID shim on teh bottom like Liam said. Help springs won't work with PSS10 unless you convert to linear. Or, I guess, you could put them on the bottom of the PSS spring where it's 60mm ID - are your helpers 60mm as well?

Edit: In your attached pic, it looks like you already have a shim in the assembly - the cad plated (gold color) factory one that the bump stop hits. That should have provided enough height. I can't believe PSS10 maxed out, still wouldn't get to 13.5" even with the reduced stack height of TMS plates. The pic isn't the best, so maybe I'm not seeing what I'm thinking.

Your upper spring pad looks old. If so, a fresh one would be thicker and might get you over 13.5" all on its own. And provide some more comfort?

I’ll have to pull the PSS10s to get a better idea of what’s going on..maybe this summer. Yeah, I was thinking about adding the helpers at the bottom, and mine are 60mm (was going to do a linear spring conversion a while back but never went thru with it). Will order new spring pads.

My other options are probably to do a linear spring conversion with 350/600 or 350/650 springs for flat ride, after I figure out what length the front springs need to be. Or, just throw on B6s with Eibach springs and TMS camber plates. The PSS10s have around 40k miles on them, so I’m not really sure if I should keep running them or replace. I can keep running the TMS plates since I have a rebuild kit.

[Tbonem3]

TMS includes a 1/2" spacer that would go beween damper shaft's shoulder and bottom of camber plate/top perch.

Yes, you can shim things. Either like I said above or you could add a 60mm ID shim on teh bottom like Liam said. Help springs won't work with PSS10 unless you convert to linear. Or, I guess, you could put them on the bottom of the PSS spring where it's 60mm ID - are your helpers 60mm as well?

Edit: In your attached pic, it looks like you already have a shim in the assembly - the cad plated (gold color) factory one that the bump stop hits. That should have provided enough height. I can't believe PSS10 maxed out, still wouldn't get to 13.5" even with the reduced stack height of TMS plates. The pic isn't the best, so maybe I'm not seeing what I'm thinking.

Your upper spring pad looks old. If so, a fresh one would be thicker and might get you over 13.5" all on its own. And provide some more comfort?

[SQ13]

That's about how my car looked with my old PSSs. Yeah, even maxed out it's still a bit low, I had the same problem. You could try using an energy suspension coil spring isolator, you can get them in a bunch of different sizes (thicknesses). You can slap it on the top or bottom of the spring and it will give you more ride height. I use one on my car and they work good.

https://www.energysuspensionparts.com/9.6103

Could I also do the same thing with helper springs? I have a set of Hyperco helper springs sitting in a box. I think the compressed height is around 0.5”, so that should help me get the ride height I’m wanting.

[SQ13]

SQ13 Wow I'm surprised. It must be to how thin the TMS camber plates are (you have TMS plates now SQ?). You could easly shim them. Did you install the TMS plates with the thick spacer that TMS includes?

Yes, have TMS street plates. This is the only photo I have of them off the car. Not sure what spacer you’re talking about. Re shims, could I add a shim in between the camber plates and upper spring perches?

[liam821]

So I actually have the fronts maxed out on ride height, and I still can’t get to 13.5”. The ride feels very complaint, but I don’t have anything to compare it to except the MCS 2WNR setup on my other car, which rides pretty harshly. The ride height is what annoys me the most.

That's about how my car looked with my old PSSs. Yeah, even maxed out it's still a bit low, I had the same problem. You could try using an energy suspension coil spring isolator, you can get them in a bunch of different sizes (thicknesses). You can slap it on the top or bottom of the spring and it will give you more ride height. I use one on my car and they work good.

https://www.energysuspensionparts.com/9.6103

[Tbonem3]

SQ13 Wow I'm surprised. It must be to how thin the TMS camber plates are (you have TMS plates now SQ?). You could easly shim them. Did you install the TMS plates with the thick spacer that TMS includes?

[SQ13]

As long as your car isn't slammed, the PSS10s are great. They're a bit soft, IMHO, so ride height is needed to keep out of the pump stops. But other than that, they ride really well.

So I actually have the fronts maxed out on ride height, and I still can’t get to 13.5”. The ride feels very complaint, but I don’t have anything to compare it to except the MCS 2WNR setup on my other car, which rides pretty harshly. The ride height is what annoys me the most.

[SQ13]

Anyone with B6s, Eibach springs, and TMS street camber plates willing to share a photo of their car? Just wanna see what the ride height is like. I imagine this setup won’t be as harsh as the PSS10s?

[liam821]

I shouldn’t have opened this thread. Now I’m looking at replacing my PSS10s with B6s or Koni Yellows + Eibach springs.

As long as your car isn't slammed, the PSS10s are great. They're a bit soft, IMHO, so ride height is needed to keep out of the pump stops. But other than that, they ride really well.