Are the bilstein B8s too harsh?

[rkulman]

I just spent $560 including tax for Koni's from Tire Rack.

[kolosy]

Same (from ecs), assuming they ever ship the shocks.

[bk94si]

I don't know the history of my car, having only owned it for a couple of weeks. I was under the car checking if anything was going on with the differential mount (looks okay). I looked at the rear shocks while I was under the car and mine are Bilstein and the shock bodies are white. Does anyone know what they are? Stock? I'm thinking stock would be black? I doubt B8 because the ride does not feel especially harsh but maybe my idea of harsh is different than others.

[GuillermoJRocha]

I wouldn't pay that much for a set of Koni struts/shocks either.

Anyhow, coming from B6 with stock springs to Konis with the stock springs, I had some personal experience with both. In my humble opinion as a seasoned driver, I really didn't feel that it was my cup of tea...

I'm testing out the B6s and with 2 days of normal daily driving, I love them on the freeway but not on rough roads. My Z3 has the black series Powerflex bushings and with the B6s on, I'm now thinking of going down to B4s or KYBs, nothing less that that. Sachs is the equivalent of a Monroe or Gabriel shock. Don't waste your money on Sachs because BMW uses them to be replaced and make money.

I have the B8s on my 330i and it feels totally different. It's a nice firm ride on a heavier an longer wheel base car. The Z3 definitely needs the B4 with poly bushings all the way around.

I wonder if I could use the B4s or KYbs with lowering springs. Does anyone know?

[cleanerPA]

Last year, I replaced the stock Sachs/BMW struts and shocks with Bilstein B6 all around- new hardware, strut mounts, etc. For whatever reason, the new springs made the car look like a lifted 4x4. Pulled the new springs, reinstalled the 100k mile stock springs, which dropped it a little, but still looked lifted. Didn't drive the car much last year. This year, the car does not look lifted any longer, so it took some time with weight on the suspension in order to settle the Bilsteins.

The B6 on stock springs rides like a luxury car- soaks up the bumps far better than the Sachs dampers. Grip seems to be just as good. I love the improvement in ride quality. I don't know how much difference the new Michelin PS4S made over the old PSS.

[Hoyt Clagwell]

Last year, I replaced the stock Sachs/BMW struts and shocks with Bilstein B6 all around- new hardware, strut mounts, etc. For whatever reason, the new springs made the car look like a lifted 4x4. Pulled the new springs, reinstalled the 100k mile stock springs, which dropped it a little, but still looked lifted. Didn't drive the car much last year. This year, the car does not look lifted any longer, so it took some time with weight on the suspension in order to settle the Bilsteins.

The B6 on stock springs rides like a luxury car- soaks up the bumps far better than the Sachs dampers. Grip seems to be just as good. I love the improvement in ride quality. I don't know how much difference the new Michelin PS4S made over the old PSS.

What are you running for suspension bushings? When I first bought my car, it was stock all around and I thought that I would need stiffer shocks as the ride was too boaty for my liking. After replacing all of the suspension related bushings, the car feels pretty stiff. I wouldn't want it much firmer and I do like a firm ride.

In short, I think that it would be very helpful if we cited the type of bushings we are running as well as the shocks and springs. Its difficult to see a pattern in people's experience without this info.

I found Michelin PS to have a softer ride than the Bridgestone Potenzas that I have on now. I prefer the Bridgestones.

[pepz]

I should be able to provide my opinion shortly.I'm finishing up installing B6s in the front and B8s in the rear of my 3.0 roadster. I found out Bilstein doesn't make a B6 for the non M rear. Using new OE springs and no lowering. I kept going back and forth between B4 and B6/B8s and decided on the latter. Hopefully, I won't be disappointed.

[pepz]

After reading some comments on B6 harshness, I went and re-read the description on them -Z3 6 Cylinder Bilstein Shock Set (Set = 2 front + 2 rear). fits all Z3 Roadster 6 cylinder cars from 96 up. Does not fit M cars. Includes top nuts and rear lower shock washers. The stock rear dust boots are re-used. The Bilstein Heavy Duty (HD) Shock is designed for use with stock springs. These shocks provide improved handling and stability without sacrificing ride comfort. I'll know soon, if this is true or not.

[pepz]

I just took my first ride with the newly installed B6/B8s and am very pleased with the ride. I took roads that had me going over manhole covers, railroad tracks and bumps. The car has a very solid feel to it. I've owned the car since it came off lease back in '04 with 17,000 miles on it. The car never felt so solid. Especially around curves. The other thing is no more rear end squat when flooring it from a stop. It always did that and I hated it. There is a little more chassis/body noise in the 22 yo car going over the above mentioned road conditions, but you don't feel it in your arse. Those stating a harsh ride may have gone with stiffer and shorter springs or more poly bushings then I did, or maybe Bilstein has just improved these struts/shocks over the years. Anyways, I'll post a complete thoughts on my total suspension upgrade besides the struts/shocks and springs. So far, I like the Bilsteins.

[Hoyt Clagwell]

I just took my first ride with the newly installed B6/B8s and am very pleased with the ride. I took roads that had me going over manhole covers, railroad tracks and bumps. The car has a very solid feel to it. I've owned the car since it came off lease back in '04 with 17,000 miles on it. The car never felt so solid. Especially around curves. The other thing is no more rear end squat when flooring it from a stop. It always did that and I hated it. There is a little more chassis/body noise in the 22 yo car going over the above mentioned road conditions, but you don't feel it in your arse. Those stating a harsh ride may have gone with stiffer and shorter springs or more poly bushings then I did, or maybe Bilstein has just improved these struts/shocks over the years. Anyways, I'll post a complete thoughts on my total suspension upgrade besides the struts/shocks and springs. So far, I like the Bilsteins.

Do you have any poly bushings? If so, where and what durometer? Thanks.

[BUCK57]

Any new shocks/bushings on our old cars is a improvement. Have had them all on my toys for the last 50 years. Current 01 M is B8 with powerflex purple all around. Good mounts, 3:73 dif, 40 precent lock up. What ever your choice is, drive it like you stole it! The Z3 platform is good, is it great? With the right mods, maybe for the money.
I will say this, sure is fun. Me now on Hawaii Island, I don't have the long roads of the CA mountains. However the short roads that are 5 miles away are spectacular with power and well handling 01 M Roadster. I don't get da coupe people, they can't drop da top😊

[pepz]

Do you have any poly bushings? If so, where and what durometer? Thanks.

I was leery of going with a lot of poly for NVH reasons. I did the IE subframe bushes back in '09. I did do Powerflex 80a on the sway bars and think that is helping a lot with the cornering improvements I am noticing. I didn't put in the Turner Motorsports monoball FCABS. I just couldn't justify the price and the front suspension kit I purchased already came with FCABS. I was also a little concerned using poly on the trailing arms, so I put in new rubber there and on the diff. Those bushings where in pretty bad shape. The diff bushing is $360...crazy. I might do more poly in a future upgrade, but didn't want to introduce too many new improvements at one time. I would say the slight NVH increase I have now is from the car just being far more solid/ridged than with the OE setup. However, the handling all the way around far outweighs the slight increase in NVH. I was really concerned with the Bilsteins after hearing about harshness. I am very pleased with them, but I did stay with OE springs. So maybe the harshness was installing them with lowering and stiffer springs. I find the setup with OE springs just right for me. Only complaint with the Bilsteins and I've read they will settle back down, is that the car is about1/4 inch higher than OE. I've only had one short ride. I'll be able to explain the changes in the handling with more driving. Now for new tires.

[Hoyt Clagwell]

I was leery of going with a lot of poly for NVH reasons. I did the IE subframe bushes back in '09. I did do Powerflex 80a on the sway bars and think that is helping a lot with the cornering improvements I am noticing. I didn't put in the Turner Motorsports monoball FCABS. I just couldn't justify the price and the front suspension kit I purchased already came with FCABS. I was also a little concerned using poly on the trailing arms, so I put in new rubber there and on the diff. Those bushings where in pretty bad shape. The diff bushing is $360...crazy. I might do more poly in a future upgrade, but didn't want to introduce too many new improvements at one time. I would say the slight NVH increase I have now is from the car just being far more solid/ridged than with the OE setup. However, the handling all the way around far outweighs the slight increase in NVH. I was really concerned with the Bilsteins after hearing about harshness. I am very pleased with them, but I did stay with OE springs. So maybe the harshness was installing them with lowering and stiffer springs. I find the setup with OE springs just right for me. Only complaint with the Bilsteins and I've read they will settle back down, is that the car is about1/4 inch higher than OE. I've only had one short ride. I'll be able to explain the changes in the handling with more driving. Now for new tires.

Thanks for the info. I'm just trying to get a good sense of which shocks to go to when mine need replacing. I believe mine are OE replacements since they are working fine. (they are black and there's no brand name on them that I can see) I've got the ZM FCABS with Powerflex blue swaybar bushings up front and AKG black 75D RSFBs and RTABs + Powerflex blue swaybar bushings out back. 'stock springs all around.

Installing these bushings made a huge difference in the firmness of the ride. It's really very firm without being jarring except on extremely hard edged bumps. I wouldn't want it much firmer and I like a taught suspension. At this point I'm leaning towards the B4s. I gather that they are slightly stiffer than stock and last a long time, so good value.
It looks to me like there is a big difference in percepted ride quality between various shocks depending on the type of bushings people are running. 'seems like hard shocks with OE bushings vs OE shocks with poly bushings or hard shocks with poly bushings are all going to be very different. (not to mention springs)

As far as NVH goes, my set-up does add some. The extremely hard poly in the rear does creak some over very low-speed bumps and irregular road surfaces. At driving speed, I can't hear them. Personally, it doesn't bother me. I'm very happy with the ride quality and handling. I may go from the ZM rubber FCABs to poly but I'm in no hurry.

[pepz]

Thanks for the info. I'm just trying to get a good sense of which shocks to go to when mine need replacing. I believe mine are OE replacements since they are working fine. (they are black and there's no brand name on them that I can see) I've got the ZM FCABS with Powerflex blue swaybar bushings up front and AKG black 75D RSFBs and RTABs + Powerflex blue swaybar bushings out back. 'stock springs all around.

Installing these bushings made a huge difference in the firmness of the ride. It's really very firm without being jarring except on extremely hard edged bumps. I wouldn't want it much firmer and I like a taught suspension. At this point I'm leaning towards the B4s. I gather that they are slightly stiffer than stock and last a long time, so good value.
It looks to me like there is a big difference in percepted ride quality between various shocks depending on the type of bushings people are running. 'seems like hard shocks with OE bushings vs OE shocks with poly bushings or hard shocks with poly bushings are all going to be very different. (not to mention springs)

As far as NVH goes, my set-up does add some. The extremely hard poly in the rear does creak some over very low-speed bumps and irregular road surfaces. At driving speed, I can't hear them. Personally, it doesn't bother me. I'm very happy with the ride quality and handling. I may go from the ZM rubber FCABs to poly but I'm in no hurry.

I really was going back and forth between the B4s and the B6/B8 setup. I'm happy with the B6/B8 but probably would have gone with the B4s if I had as much hard poly bushings as you do. Bilstein states the B4s are 10% stiffer than OE and the B6/B8s are 15% stiffer. I find this to be a very vague comparison. I haven't read that the B4s raise the car with OE springs like the B6/B8, so you might need to research that unless you decide to go with lower springs. My NVH is more noise related. I'm hearing the body/chassis make a soft shuddering sound (slightly more than before the suspension upgrades) when hitting a pot hole, but I feel nothing. The Bilstiens are completely absorbing the impact. That is actually better than the OE Sachs where I would feel the impact as well.

[Hoyt Clagwell]

I really was going back and forth between the B4s and the B6/B8 setup. I'm happy with the B6/B8 but probably would have gone with the B4s if I had as much hard poly bushings as you do. Bilstein states the B4s are 10% stiffer than OE and the B6/B8s are 15% stiffer. I find this to be a very vague comparison. I haven't read that the B4s raise the car with OE springs like the B6/B8, so you might need to research that unless you decide to go with lower springs. My NVH is more noise related. I'm hearing the body/chassis make a soft shuddering sound (slightly more than before the suspension upgrades) when hitting a pot hole, but I feel nothing. The Bilstiens are completely absorbing the impact. That is actually better than the OE Sachs where I would feel the impact as well.

OK thanks. At this point I'll probably go with the B4s when the time comes that I need new shocks. I'll stick with the stock springs since I don't want to lower the car. My wife and I go for extended cruises and road trip vacations and we do encounter some less than ideal roads sometimes.

[cleanerPA]

What are you running for suspension bushings? When I first bought my car, it was stock all around and I thought that I would need stiffer shocks as the ride was too boaty for my liking. After replacing all of the suspension related bushings, the car feels pretty stiff. I wouldn't want it much firmer and I do like a firm ride.

In short, I think that it would be very helpful if we cited the type of bushings we are running as well as the shocks and springs. Its difficult to see a pattern in people's experience without this info.

I found Michelin PS to have a softer ride than the Bridgestone Potenzas that I have on now. I prefer the Bridgestones.

Stock suspension bushings and all new. I've run Michelin Pilot Sport X (the X being whatever generation) from the original Pilot Sport (1) that were on the car to the PS4S on there currently.

I found the stock Sachs shocks to be punishingly stiff, I wonder if they were not working properly.

I didn't lose any handling, it seems, so with the softer ride now, I can see why people want to stiffen it up.

I also noticed, when changing to Pilot Super Sports, that the grip of the rubber increased to the point where I was feeling bushing deflection during cornering.

- - - Updated - - -

I really was going back and forth between the B4s and the B6/B8 setup. I'm happy with the B6/B8 but probably would have gone with the B4s if I had as much hard poly bushings as you do. Bilstein states the B4s are 10% stiffer than OE and the B6/B8s are 15% stiffer. I find this to be a very vague comparison. I haven't read that the B4s raise the car with OE springs like the B6/B8, so you might need to research that unless you decide to go with lower springs. My NVH is more noise related. I'm hearing the body/chassis make a soft shuddering sound (slightly more than before the suspension upgrades) when hitting a pot hole, but I feel nothing. The Bilstiens are completely absorbing the impact. That is actually better than the OE Sachs where I would feel the impact as well.

I don't think you should second guess your decision- the B6/B8 shocks seem to be better built, overall. I've used the B4s in the past on a different car, and their longevity wasn't much better than the OE shocks- about 30-40k miles. The Bilstein B6/B8 seem to last much longer without degradation.