[M-technik-3]

prices are vastly different in cost from one vendor to another.

[whyzee125]

Where are they on sale?

[M-technik-3]

Just about everywhere is having a 20% off sale. Bimmer World is cheapest I have seen for e9X series.

[Vivek.]

$590 on Bimmerworld for our cars. That's less than I paid for my e30 8 years ago. Koni yellows are by far the best dampers without going full coils--both comfort and performance are far superior to Bilstein.

[M-technik-3]

Sad part is I just paid that for OEM M Sports last fall. But I could not wait and did not want coil-overs. Yeah I still have Koni's in my E30 as well. The e30M has J Stock Billies.

[2one3E90]

Originally Posted by Vivek.

$590 on Bimmerworld for our cars. That's less than I paid for my e30 8 years ago. Koni yellows are by far the best dampers without going full coils--both comfort and performance are far superior to Bilstein.

How comfort and performance far super than bilstein b12 prokit?

[Vivek.]

Originally Posted by 2one3E90

How comfort and performance far super than bilstein b12 prokit?

I don't have specific experience with B12 prokit. In general, gas-charged dampers like Bilstein ride more harshly yet cannot keep up as effectively when pushed hard when compared to oil-filled dampers like Koni. Additionally, the adjustability of Koni Sport dampers allow for more fine tuning if you want the ride to be softer or performance to be sharper. On a Bilstein damper, you get what you get.

[2one3E90]

Originally Posted by Vivek.

I don't have specific experience with B12 prokit. In general, gas-charged dampers like Bilstein ride more harshly yet cannot keep up as effectively when pushed hard when compared to oil-filled dampers like Koni. Additionally, the adjustability of Koni Sport dampers allow for more fine tuning if you want the ride to be softer or performance to be sharper. On a Bilstein damper, you get what you get.

Thanks but whats more reliable for rougher roads? Isnt the konis gonna be more prone to blowing or failing?

[Vivek.]

Originally Posted by 2one3E90

Thanks but whats more reliable for rougher roads? Isnt the konis gonna be more prone to blowing or failing?

Not in my experience. Both have a lifetime warranty for the original purchaser.

All else equal, it's easier for a gas to escape from a tube than an oil, and while Bilstein uses oil as well they rely on the high-pressure gas charge to perform as intended.

[dmatre]

Originally Posted by Vivek.

I don't have specific experience with B12 prokit. In general, gas-charged dampers like Bilstein ride more harshly yet cannot keep up as effectively when pushed hard when compared to oil-filled dampers like Koni. Additionally, the adjustability of Koni Sport dampers allow for more fine tuning if you want the ride to be softer or performance to be sharper. On a Bilstein damper, you get what you get.

I have to disagree, somewhat.

In my experience (Koni Sports on 2 cars, including presently on the E90; Bilstein on 2 cars):
- Bilstein are harsher over broken pavement at low (commuting) speeds, but more compliant at high speeds (highway driving). They seem to allow good compliance on the highway, but once you bend it into a curve, they are very solid.
- Koni Sport seem more 'linear' in their performance. They are less harsh than Bilstein at commuting speeds, less compliant at highway speeds. Bend them into a curve and they behave the same way that they do at low and high speeds.

I went with Koni on the E90 because of the low-speed harshness experienced with the Bilsteins (Audi S4, Volvo S80) - this would be a deal-breaker on my morning/evening commute.

But, to be honest, they are both great products, and you won't go wrong with either one. Both are far superior to the OEM shocks.

[Vivek.]

Originally Posted by dmatre

I have to disagree, somewhat.

In my experience (Koni Sports on 2 cars, including presently on the E90; Bilstein on 2 cars):
- Bilstein are harsher over broken pavement at low (commuting) speeds, but more compliant at high speeds (highway driving). They seem to allow good compliance on the highway, but once you bend it into a curve, they are very solid.
- Koni Sport seem more 'linear' in their performance. They are less harsh than Bilstein at commuting speeds, less compliant at highway speeds. Bend them into a curve and they behave the same way that they do at low and high speeds.

I went with Koni on the E90 because of the low-speed harshness experienced with the Bilsteins (Audi S4, Volvo S80) - this would be a deal-breaker on my morning/evening commute.

But, to be honest, they are both great products, and you won't go wrong with either one. Both are far superior to the OEM shocks.

Nice, thanks for elaborating. The harshness I was referring to was mostly experienced at slow speeds. Good points about comfort at higher speeds, I'd agree based on my experience.

Do you find Bilstein or Koni to be superior in terms of high speed cornering?

[bluewater328]

For the record, Bilstein is having a sale as well on the usual suspects like ECS/Turner.

[dmatre]

Originally Posted by Vivek.

Nice, thanks for elaborating. The harshness I was referring to was mostly experienced at slow speeds. Good points about comfort at higher speeds, I'd agree based on my experience.

Do you find Bilstein or Koni to be superior in terms of high speed cornering?

I've never had both on the same car.

My gut feeling is that the Bilsteins may hold a slight edge in high speed handling. That being said, the Konis carried me to several Local, Divisional, and National trophies, so they're no slouch either.

The advantage of the Konis is the ability to adjust the rebound- which allows one to adjust the turn-in behavior. Stiffer rear rebound = less understeer at turn-in. Stiffer front rebound = more understeer at turn-in.

[2one3E90]

Originally Posted by dmatre

I've never had both on the same car.

My gut feeling is that the Bilsteins may hold a slight edge in high speed handling. That being said, the Konis carried me to several Local, Divisional, and National trophies, so they're no slouch either.

The advantage of the Konis is the ability to adjust the rebound- which allows one to adjust the turn-in behavior. Stiffer rear rebound = less understeer at turn-in. Stiffer front rebound = more understeer at turn-in.

Was it these specific Konis? and on what car what setuo?

[tlow98]

Originally Posted by dmatre

I have to disagree, somewhat.

In my experience (Koni Sports on 2 cars, including presently on the E90; Bilstein on 2 cars):
- Bilstein are harsher over broken pavement at low (commuting) speeds, but more compliant at high speeds (highway driving). They seem to allow good compliance on the highway, but once you bend it into a curve, they are very solid.
- Koni Sport seem more 'linear' in their performance. They are less harsh than Bilstein at commuting speeds, less compliant at highway speeds. Bend them into a curve and they behave the same way that they do at low and high speeds.

I went with Koni on the E90 because of the low-speed harshness experienced with the Bilsteins (Audi S4, Volvo S80) - this would be a deal-breaker on my morning/evening commute.

But, to be honest, they are both great products, and you won't go wrong with either one. Both are far superior to the OEM shocks.

Agree whole-heartedly. My experience with both products is the same.

With both being as good as they are I would ask myself how important is comfort at low speeds? Personally, I would never commute in LA on Bilsteins. Much too harsh.

I always wanted to try the FCM Bilstein revalves. Likely the best of both worlds.

[dmatre]

Originally Posted by 2one3E90

Was it these specific Konis? and on what car what setuo?

Both Konis were Koni Sport (Yellow).
- Car 1: 1986 Acura Integra, used originally with stock suspension, autocrossing in E-Stock. Later upgraded with Lightspeed torsion bars/springs/sways and ran Street-Prepared and did a lot of track events.
- Car 2: 2011 328i (E90). Presently my daily driver. Purchased Pro-Kit (Koni Sport + Eibach springs).

Bilsteins were B6/B8.
- Car 1: B8 on Audi S4 with H&R Lowering Springs. Daily driver.
- Car 2: B6 on Volvo S80, all else stock from factory. Daily driver.

[2one3E90]

Originally Posted by dmatre

Both Konis were Koni Sport (Yellow).
- Car 1: 1986 Acura Integra, used originally with stock suspension, autocrossing in E-Stock. Later upgraded with Lightspeed torsion bars/springs/sways and ran Street-Prepared and did a lot of track events.
- Car 2: 2011 328i (E90). Presently my daily driver. Purchased Pro-Kit (Koni Sport + Eibach springs).

Bilsteins were B6/B8.
- Car 1: B8 on Audi S4 with H&R Lowering Springs. Daily driver.
- Car 2: B6 on Volvo S80, all else stock from factory. Daily driver.

Hows the handling of the e90 with the yellows? Would u take it to the track?

[dmatre]

Originally Posted by 2one3E90

Hows the handling of the e90 with the yellows? Would u take it to the track?

Absolutely I would. I would have taken the car to the track in stock form as well.

I've done Performance Delivery, the Performance Driving School, M-School at the BMW Performance Center. These cars are quite capable on track as delivered from the factory.

If tracking, better brakes (Performance Friction, Hawk, etc) are higher priority than better shocks.

I can say that with the Konis, the car is simply more capable. On backroads around here, my limiting factor on speed is how comfortable the car is at that speed. With the Konis, the car is far more 'comfortable' (controllable - less, or more controlled, body motion) at the same speeds, and driving at the same 'comfort level' results in higher speeds over the same roads.

One significant improvement is the behavior of the rear in the event of a mid-corner bump. With the stock shocks, the rear tried to move 1/2-lane to the outside if cornering hard and hitting a bump mid-corner. With the Konis, the car just absorbs the bump and goes on with no drama.

If you PM me, I can send you a short video showing exactly the behavior I'm referring to. You can actually see the rear of the car jump left while the front is still planted and unperturbed by the same bump.

[lowrydr310]

Originally Posted by dmatre

- Koni Sport seem more 'linear' in their performance. They are less harsh than Bilstein at commuting speeds, less compliant at highway speeds. Bend them into a curve and they behave the same way that they do at low and high speeds.

Originally Posted by tlow98

Personally, I would never commute in LA on Bilsteins. Much too harsh.

These two reasons now have me leaning towards the Koni yellows. I highly value comfort at normal speeds on lousy roads since that's where my car spends 90% of its time. I also value durability/longevity and I have read claims that the Koni's aren't as durable as the Bilsteins and may need replacement sooner. Is there any truth to this?

Originally Posted by dmatre

Absolutely I would. I would have taken the car to the track in stock form as well.

...

I can say that with the Konis, the car is simply more capable.

I just replaced front struts recently with Bilstein B4 for sport suspension, using the original sport springs that came with my 330i. Now the rear shocks need to be replaced since one is slightly leaking and the bump stops are crumbly. I had planned on installing Bilstein B8 but now I'm second guessing myself. Would I be better off with the Koni yellows especially since they're on sale, or go cheaper and just stick with new B4s to match the front for now?

[dmatre]

Originally Posted by lowrydr310

These two reasons now have me leaning towards the Koni yellows....
... Would I be better off with the Koni yellows especially since they're on sale, or go cheaper and just stick with new B4s to match the front for now?

Unfortunately, I can't tell you whether you'd be better off with Konis than B4's, because everyone has their own preferences on the sport/comfort scale. I'm willing to sacrifice some comfort for control, but I won't accept a harsh ride over broken pavement.

That being said, we have B4's on the wife's Benz, and they are quite capable on their own (and likely you have found them an upgrade over the OEM fronts). The B4's should give you similar durability to the B6/B8 and Koni.

If your preference leans to comfort on your daily commute, then B4's are not a bad choice. They are still very competent, they can be tracked (as can the less-than-stellar OEM shocks/struts). However, on the track you may wish you had chosen the B6/Koni. Just as when riding over broken pavement every day on B6/Koni you may wish you had purchased B4's.

In the end, it's just a car, and it has to meet your expectations - but those have to be reasonable. If you absolutely need to have comfortable ride and control on track, then you need to jump to the mega-bux category and invest in a set of Penske/JRZ 3-way adjustable shocks (close to $1000 per corner). They will allow you to adjust high-speed compression, low-speed compression, and rebound to get the results you desire.

Life is about compromises. So consider where your taste is regarding comfort/sport/budget, then choose according to your personal requirements.
With the choices you have in front of you, there are no losers.

One other option to throw out there: The Koni equivalent to the B4 is their STR-T line. They are the same shock as the Sport, but valved a bit softer. They are also an upgrade over stock, but a closer-to-oem ride than the B6/Koni Sport.

There are no 'losers' in the products you selected. All should have a similar life, and all come with a lifetime warranty.

[tlow98]

I would not put b4s on the front and b8s on the rear as they’re very different designs and that would lead to odd handling behavior. Since you have b4s on the front of match those in the rear. B4s are very good.

If you were replacing them all I’d say konis. On the durability factor - hard to say but I’ve never had issues with the konis I’ve installed on all my cars. B4s will last a long time. There are too many unknowns to gushed this.

Also be sure to replace your bump stops. Made a huge difference on my car as these cars spend so much time in them!

[lowrydr310]

Originally Posted by tlow98

I would not put b4s on the front and b8s on the rear as they’re very different designs and that would lead to odd handling behavior. Since you have b4s on the front of match those in the rear. B4s are very good.

If you were replacing them all I’d say konis. On the durability factor - hard to say but I’ve never had issues with the konis I’ve installed on all my cars. B4s will last a long time. There are too many unknowns to gushed this.

Also be sure to replace your bump stops. Made a huge difference on my car as these cars spend so much time in them!

I wasn't clear I know, but if I put B8s on the back I would be upgrading the struts to match (despite them being fairly new.) I am just going to stick with the B4 shocks for now to match what I have. Less work and cheaper and more ideal for my needs.

Yeah my rear bump stops are trashed so they'll be getting replaced.