[mlifxs]

Hi, I have a 328i with ZSP springs. I'm thinking about the future ... ie when it comes time to change dampers, what are reasonable options for a daily driver / noob autox'r.

My car has 125k miles on it and I'm not looking to spend $$$$, so dampers and springs (or just keep my ZSP springs) are one thought. I intend to focus on the damper characteristics, thinking that will be what matters most, though maybe there are some benefits to changing springs, away from ZSP?

Most aftermarket springs seem to focus on lowering, in addition to other characteristics. Really, I don't care if I lower my car and would rather not if there are negative trade-offs. Lowering would only make sense if it improved the handling characteristics...and I'm skeptical that benefits outweigh trade-offs (am I wrong?)

So...getting to my title question are there options in terms of spring rates, for those of us not looking to lower?

[cvc 22349a]

I didn't want to lower my car either; that's why I tried a few spring/shock combos before KW sc. Lowering the car .5-1" definately improves handling and isn't that much. Somewhat stiffer springs with a good damper also improves handling. You know what I think but that Bilstein b12 kit sounds good too with a stronger front roll bar. If autox is really important I'd want linear rate springs though so that brings me back to my setup or look at tck/GC but those will give a firm daily ride.

[jjellyneck]

You know the usual Eibach kits (which are good), the BMWPS...then there are ideas such as:
*BMWPS springs with Bilstein HD or Sport dampers
*Swift springs on a relatively soft rate with Bilstein dampers (HPA pairs them with Koni)

The BMWPS does not lower very much, and I suspect you can get a Swift that is likewise similar in ride height.

[cvc 22349a]

Swift sport springs have a higher rate and lower the car more than bmwps springs. Dinan springs are an option too.

[mlifxs]

Originally Posted by cvc 22349a

I didn't want to lower my car either; that's why I tried a few spring/shock combos before KW sc. Lowering the car .5-1" definately improves handling and isn't that much. Somewhat stiffer springs with a good damper also improves handling. You know what I think but that Bilstein b12 kit sounds good too with a stronger front roll bar. If autox is really important I'd want linear rate springs though so that brings me back to my setup or look at tck/GC but those will give a firm daily ride.

Thanks, I know you worked through a lot of this.

Our roads here are relatively smooth, so I've thought "why not focus on dampers with more rebound control" and possibly pair with higher rate springs, as you suggest. But I think you had issues with suspension travel when you did the Koni / BMWPS springs(?)

Regarding "not lowering" ..so many threads regarding lowering are colored with the aesthetics of lowering and less discussion about handling benefit. Then there are threads about needing corrections to sway links, rear toe links, ride quality, speed bumps yadayada... Just makes me wonder "why not keep it simple if my roads aren't going to punish me?" So, I've thought about the Koni's with some spring option, higher rate but same ride height to avoid any suspension travel issue...then adjust the dampers until everything feels right.

Your current set up certainly makes sense as well, to be able to adjust pretty much everything until you like it...and valved to work with the linear springs.

[cvc 22349a]

Dinan and bmwps barely lower the car .5" if that. Eibach a little more maybe. Swift h&r even more I think. Paired with stock strut bodies they all reduce compression travel which is what I complained about with the ps/Koni. If I lived in Nevada or some state with good roads it would have been fine. Ca roads suck! At least ps and Dinan springs come with shorter bumpstops when using koni's.
I don't think you're going to get much of a handling benefit by just switching dampers and not springs.

[jjellyneck]

Originally Posted by cvc 22349a

Swift sport springs have a higher rate and lower the car more than bmwps springs. Dinan springs are an option too.

I was thinking that a Swift spring existed....that offered the same ride height or slightly lower than the performance suspension.
FL roads aren't nearly as severe as those in San Fran or Houston. When living in Austin, I wanted a stiffer and better handling suspension...but after moving to the harsher roads of Houston I am leaning toward better damping of small constant bumps and ever-present lunar landing surfaces.

[mike-y]

Originally Posted by cvc 22349a

I don't think you're going to get much of a handling benefit by just switching dampers and not springs.

If you get a good sports damper, like a koni yellow or Bilstein, you will feel a noticeable difference when paired with the factory springs.

That's exactly what I did, since I did not want to lower my car, due to the way my driveway is designed. I kept the ZSP springs and installed koni yellows. There was a noticeable difference over stock.

[cvc 22349a]

Originally Posted by mike-y

If you get a good sports damper, like a koni yellow or Bilstein, you will feel a noticeable difference when paired with the factory springs.

That's exactly what I did, since I did not want to lower my car, due to the way my driveway is designed. I kept the ZSP springs and installed koni yellows. There was a noticeable difference over stock.

I agree Mike. I liked the koni's with zsp springs (better than koni/ps for ride quality) but the op has bmwps dampers not the oem dampers so I don't know that he'll get a significant improvement in handling which seems to be what he's after

[cvc 22349a]

Originally Posted by jjellyneck

I was thinking that a Swift spring existed....that offered the same ride height or slightly lower than the performance suspension.
FL roads aren't nearly as severe as those in San Fran or Houston. When living in Austin, I wanted a stiffer and better handling suspension...but after moving to the harsher roads of Houston I am leaning toward better damping of small constant bumps and ever-present lunar landing surfaces.

Oem zsp springs with Koni sport or Bilstein hd if you don't want to go w/a c/o imho. There's a guy in la with swift/Koni. Read his thread about ride comfort.

[mbanks21]

I'll be selling my E90 330i sport suspension soon not sure it fits your car though but I'm in FL

[mlifxs]

Originally Posted by mbanks21

I'll be selling my E90 330i sport suspension soon not sure it fits your car though but I'm in FL

thanks, it would probably fit, but I'm on the BMW performance suspension now, which was a step up from my original sport suspension.

cvc, to your point, yes, if there is noticeable improvement with a spring upgrade when I change dampers, I'm interested since it will be better and because minimal additional labor.

So are springs a benefit due to higher spring rate effects or does the lowering effect have it's own benefit?

[mike-y]

Originally Posted by cvc 22349a

I agree Mike. I liked the koni's with zsp springs (better than koni/ps for ride quality) but the op has bmwps dampers not the oem dampers so I don't know that he'll get a significant improvement in handling which seems to be what he's after

ah that's right. Very good point.

[cvc 22349a]

[QUOTE=mlifxs;15407972]thanks, it would probably fit, but I'm on the BMW performance suspension now, which was a step up from my original sport suspension.

cvc, to your point, yes, if there is noticeable improvement with a spring upgrade when I change dampers, I'm interested since it will be better and because minimal additional labor.

So are springs a benefit due to higher spring rate effects or does the lowering effect have it's own benefit?[/QUOTE]

Higher rate springs and lowering your car's center of gravity both improve handling independent of one another. If you're not going with a c/o I wouldn't use a sport spring with oem length strut bodies that lowers the car more than .5" from zsp as you lose precious compression travel. That pretty much limits your choices to BMWPS, Dinan or Eibach pro kit off the top of my head. If you do go with a c/o I wouldn't lower the car more than 1.25" from zsp as that'll adversely affect suspension geometry.

[mlifxs]

[QUOTE=cvc 22349a]

Originally Posted by mlifxs

thanks, it would probably fit, but I'm on the BMW performance suspension now, which was a step up from my original sport suspension.

cvc, to your point, yes, if there is noticeable improvement with a spring upgrade when I change dampers, I'm interested since it will be better and because minimal additional labor.

So are springs a benefit due to higher spring rate effects or does the lowering effect have it's own benefit?[/QUOTE]

Higher rate springs and lowering your car's center of gravity both improve handling independent of one another. If you're not going with a c/o I wouldn't use a sport spring with oem length strut bodies that lowers the car more than .5" from zsp as you lose precious compression travel. That pretty much limits your choices to BMWPS, Dinan or Eibach pro kit off the top of my head. If you do go with a c/o I wouldn't lower the car more than 1.25" from zsp as that'll adversely affect suspension geometry.

nice summary, thanks.

guess b12 kit gets lower center of gravity benefit while preserving suspension travel but maybe not higher spring benefit...people seem to love it, though most reviews I've read are folks upgrading from stock.

koni setups can handle higher rate springs and allow rebound adjustment, but many of those setups will sacrifice some suspension travel and ride quality, more noticeable if roads are bad.

coil setup like yours provides higher spring rate benefit along with adjustable center of gravity and rebound....and linear spring tuning. would have to decide if it's worth the plunge when my car gets to 150-160k miles....or if I cave in to temptation, early

found your comment about bmwps dampers interesting, perhaps implying? they are comparable to koni (without adjustment obviously) . am I misinterpreting?

[cvc 22349a]

Implying I don't know how much handling benefit you'll realize just switching out your PS dampers to Koni or Bilstein w/o changing springs. Implying if you don't want to change springs, just leave it alone and save your money.
Don't certain autox competitions prohibit you switching springs anyway?

[mlifxs]

Originally Posted by cvc 22349a

Implying I don't know how much handling benefit you'll realize just switching out your PS dampers to Koni or Bilstein w/o changing springs. Implying if you don't want to change springs, just leave it alone and save your money.
Don't certain autox competitions prohibit you switching springs anyway?

ok, thanks!
autox question...something I guess I should look into. I think for BMWCCA they add points for any mod and collect enough, you're in a higher class. Springs might be one of them.

[osukf09]

Do springs need to be replaced due to wear, similar to struts? I'm running BMWPS struts on zsp springs with around 70k miles on them. Not sure if they need to be replaced yet

[mlifxs]

Originally Posted by apjr09

Do springs need to be replaced due to wear, similar to struts? I'm running BMWPS struts on zsp springs with around 70k miles on them. Not sure if they need to be replaced yet

from what I've read, springs last many times longer than shocks. Don't think you would need to change them.

[osukf09]

Originally Posted by mlifxs

from what I've read, springs last many times longer than shocks. Don't think you would need to change them.

Great, thanks for the info!

[Chocolate Apocalypse]

FWIW I have the Koni/BMW PS setup w/Supreme Power perches (to get the nose down a bit) and so far its great. Went from factory sport suspension to this, doesnt lower the car much from the sport springs, maybe 1/2 inch but feels much better. More taught without being harsh, which is exactly what I wanted.

[mlifxs]

Originally Posted by Chocolate Apocalypse

FWIW I have the Koni/BMW PS setup w/Supreme Power perches (to get the nose down a bit) and so far its great. Went from factory sport suspension to this, doesnt lower the car much from the sport springs, maybe 1/2 inch but feels much better. More taught without being harsh, which is exactly what I wanted.

thanks for the info. Did you do anything with bump stops? (change them from stock)