[Thecastle]

I hope this helps others when considering Koni FSD's for their car.

A little about my car/driving environment, I have a 2011 BMW 335d with the sports suspension package and the stock 18" staggered rims and 35k miles. Living in Texas with actual first world roads I generally found the stock sport suspension with RFTs acceptable to a bit soft on undulations on the freeway where the suspension would take a couple of bounces before damping down the oscillation. In fact I generally found the sport suspension good, but a bit floaty over undulating roads, and somewhat crashy over bad hits on the freeway. It also has a lot of body roll that makes the car feel heavier than it actually is. Overall I thought the sports suspension was too soft. I frankly enjoyed driving my wife's mini cooper S more.

So time for a suspension MOD. My goal, improve handling without killing ride quality. Which meant no lowering which often screws up suspension geometry and ride quality with only an improvement in stiffness. So off went the stock RFT's and a set of Michelin Pilot Super Sports (minor change at best for ride, good improvement in grip). Then a new set of Koni FSD's with new strut and shock mounts and new front bump stops with the stock sport springs remaining in place.

I did the install job myself, and it took longer than planned. Purchased Struts/shocks from tunersports.com, and the install kit from turnermotorsports, the bump stops were unanticipated purchases.

My initial impression after completing the change over, I thought everything had been improved. Definitely more damping over slow undulations by about 25-30% which eliminated the bounciness and unpredictability of the stock ride. Also significantly less brake dive (thank goodness it could be pretty bad at times), and significantly less body roll in corners. So far so good. No more pot hole explosions. Great!

What really impressed me with the FSD's is I took a bumpy section of curvy freeway. Previously at high speeds on tight corners 80-100mph the section transitions were hard enough to cause the car to loose grip and crab sideways over the bumps. The FSDs eliminated this behavior. Instead of loosing grip on high-speed corners over bumps, the Koni's maintained good tire contact and mid corner bumps now barely disturb the car.

What I did notice initially after the suspension replacement was more high frequency "jiggle" on our concrete freeways. The suspension let in more mid frequency undulations into the car. However, after a week of driving and break in this totally went away. I suspect this was a function of the new mounts settling.

Honestly, other than its a pain to install springs on the struts, and having to spend money to do this; I really didn't detect any downsides to the Koni FSD's. They do exactly what they claim, improve/maintain the ride quality while improving the handling.

[GreekboyD]

These wouldn't be a good choice for anyone running a base suspension model. FSDs are designed specifically for BMW Sport or Performance springs. Many people opt for the yellow ones as a few have had issues with the regular ones.

[Puerto Rican 335d]

Greek I have the FSDs a on my car and the car is NON Sport. Car handles way better than OEM. I have used FSDs since 2007 I believe, and had them on my 02 MCS. they're great

[Chief Orman]

Originally Posted by Puerto Rican 335d

Greek I have the FSDs a on my car and the car is NON Sport. Car handles way better than OEM. I have used FSDs since 2007 I believe, and had them on my 02 MCS. they're great

FSDs are great.

[kg4kdn]

Originally Posted by Thecastle

I hope this helps others when considering Koni FSD's for their car.

A little about my car/driving environment, I have a 2011 BMW 335d with the sports suspension package and the stock 18" staggered rims and 35k miles. Living in Texas with actual first world roads I generally found the stock sport suspension with RFTs acceptable to a bit soft on undulations on the freeway where the suspension would take a couple of bounces before damping down the oscillation. In fact I generally found the sport suspension good, but a bit floaty over undulating roads, and somewhat crashy over bad hits on the freeway. It also has a lot of body roll that makes the car feel heavier than it actually is. Overall I thought the sports suspension was too soft. I frankly enjoyed driving my wife's mini cooper S more.

So time for a suspension MOD. My goal, improve handling without killing ride quality. Which meant no lowering which often screws up suspension geometry and ride quality with only an improvement in stiffness. So off went the stock RFT's and a set of Michelin Pilot Super Sports (minor change at best for ride, good improvement in grip). Then a new set of Koni FSD's with new strut and shock mounts and new front bump stops with the stock sport springs remaining in place.

I did the install job myself, and it took longer than planned. Purchased Struts/shocks from tunersports.com, and the install kit from turnermotorsports, the bump stops were unanticipated purchases.

My initial impression after completing the change over, I thought everything had been improved. Definitely more damping over slow undulations by about 25-30% which eliminated the bounciness and unpredictability of the stock ride. Also significantly less brake dive (thank goodness it could be pretty bad at times), and significantly less body roll in corners. So far so good. No more pot hole explosions. Great!

What really impressed me with the FSD's is I took a bumpy section of curvy freeway. Previously at high speeds on tight corners 80-100mph the section transitions were hard enough to cause the car to loose grip and crab sideways over the bumps. The FSDs eliminated this behavior. Instead of loosing grip on high-speed corners over bumps, the Koni's maintained good tire contact and mid corner bumps now barely disturb the car.

What I did notice initially after the suspension replacement was more high frequency "jiggle" on our concrete freeways. The suspension let in more mid frequency undulations into the car. However, after a week of driving and break in this totally went away. I suspect this was a function of the new mounts settling.

Honestly, other than its a pain to install springs on the struts, and having to spend money to do this; I really didn't detect any downsides to the Koni FSD's. They do exactly what they claim, improve/maintain the ride quality while improving the handling.

I wonder if the FSD's would make Greens road between JFK and Aldine Westfield any more tolerable. I think my teeth are going to rattle out of my head every time I drive that stretch

[Puerto Rican 335d]

kg4kdn just like in Puerto Rico LOL

[kg4kdn]

Originally Posted by Puerto Rican 335d

kg4kdn just like in Puerto Rico LOL

Amigo, nunca eh estado en Puerto Rico pero creo que las carriles son malo.

This road is the worst in Houston. Most are great here. When I get the FSD's, I will report back on how they do. Sounds like they work well. thank you, Castle for the great review. I was wondering if they were worth the $$. Sounds like they are.

[Thecastle]

I just got back from an over 4,000 mile trip from Houston to Yellowstone National park in Wyoming. Still like the Koni FSD's a lot. Great high speed stability as I was running the car at a constant 100mph+ for long stretches. Its pretty easy to maintain high speeds most everywhere during the drive to the park except around Denver. Heck Wyoming nothing is there to slow you done beyond the fear of getting caught :-) Same as in west texas.

soaks up most road imperfections well, and did well with lots of cargo in the trunk/back seat (tented).

My only complaint is still would like a bit more dampening over the road/bridge transitions on the interstate. Some of them can be really bad especially in Wyoming (judging by the scrape marks in the pavement and bump sign warnings). The car absorbs the initial hard impact well, but still has some additional oscillations after the initial impact. I suppose its the small price one pays for not having one's head hit the ceiling.....

Absolutely no pothole explosions, in 4K miles over some pretty bad roads. No problems handling some big hits on various highways at high speeds (for america anyway).

Still very happy with the Koni's. I probably have nearly 6k miles on them since the install..

Oh yeah, My car killed like a million bugs and the entire front end was covered by bug splatter. Lol.

[Puerto Rican 335d]

kg4kdn date una vuelta de vacaciones antes que me mude pa Santo Domingo in the next 2 years ok

[Pierre Louis]

Originally Posted by Puerto Rican 335d

Umm I ask you have you used them at anytime, I have on two different and distinctive BMW vehicles one was an 02 MCS and i left the sport springs on, two on my 11 335d (diesel engines are heavier)NON-Sport and every person that has driven both my vehicles have commended them and some have gone as far as buying. A PLACEBO effect I doubt that cause the people that drove my vehicles WERE NOT told that I had changed the shocks they came to me and asked what had I done to my car. So, I summarize your placebo effect has been eradicated. And BTW I didn't spend 1k on them I have bought them with a 15% and 20 % discount respectively, I believe since you live in Europe you had to pay the price tough luck amigo. Go ahead and buy yourself another brand if it suits you, some of us are happy and don't be a hater, it makes you look bad.

I've had great luck with Koni's and Bilstein's in the past, the Bilsteins for their gas pressure support of my old Suburban, raising the ride height a proper amount, while the Koni shocks helped tremendously with both ride and handling.

The FSD's on Axel's car were quite nice when I came to visit him and you could feel the difference from standard shocks for sure.

PL

[rogerdiaz]

Originally Posted by Thecastle

I hope this helps others when considering Koni FSD's for their car.

A little about my car/driving environment, I have a 2011 BMW 335d with the sports suspension package and the stock 18" staggered rims and 35k miles. Living in Texas with actual first world roads I generally found the stock sport suspension with RFTs acceptable to a bit soft on undulations on the freeway where the suspension would take a couple of bounces before damping down the oscillation. In fact I generally found the sport suspension good, but a bit floaty over undulating roads, and somewhat crashy over bad hits on the freeway. It also has a lot of body roll that makes the car feel heavier than it actually is. Overall I thought the sports suspension was too soft. I frankly enjoyed driving my wife's mini cooper S more.

So time for a suspension MOD. My goal, improve handling without killing ride quality. Which meant no lowering which often screws up suspension geometry and ride quality with only an improvement in stiffness. So off went the stock RFT's and a set of Michelin Pilot Super Sports (minor change at best for ride, good improvement in grip). Then a new set of Koni FSD's with new strut and shock mounts and new front bump stops with the stock sport springs remaining in place.

I did the install job myself, and it took longer than planned. Purchased Struts/shocks from tunersports.com, and the install kit from turnermotorsports, the bump stops were unanticipated purchases.

My initial impression after completing the change over, I thought everything had been improved. Definitely more damping over slow undulations by about 25-30% which eliminated the bounciness and unpredictability of the stock ride. Also significantly less brake dive (thank goodness it could be pretty bad at times), and significantly less body roll in corners. So far so good. No more pot hole explosions. Great!

What really impressed me with the FSD's is I took a bumpy section of curvy freeway. Previously at high speeds on tight corners 80-100mph the section transitions were hard enough to cause the car to loose grip and crab sideways over the bumps. The FSDs eliminated this behavior. Instead of loosing grip on high-speed corners over bumps, the Koni's maintained good tire contact and mid corner bumps now barely disturb the car.

What I did notice initially after the suspension replacement was more high frequency "jiggle" on our concrete freeways. The suspension let in more mid frequency undulations into the car. However, after a week of driving and break in this totally went away. I suspect this was a function of the new mounts settling.

Honestly, other than its a pain to install springs on the struts, and having to spend money to do this; I really didn't detect any downsides to the Koni FSD's. They do exactly what they claim, improve/maintain the ride quality while improving the handling.

Hi, what is the "install kit" you mention and do you have p/n for bumpstops? Were they OEM? I have 135,000 miles ZSP.

[DWR]

Most of my experience with Koni are with adjustables on semi-track cars Porsches and Miata. Lot of shocks now that are adjustable, but turning the dial on the Koni always seemed more predictable and therefore easier to tune.

But I have to say, on the road, Bilsteins are my favorite, by a good margin. I have put them on Volvos, Mercedes, BWMs, Porsches and the result is always the same. A smoothness that seems to be characteristic. Some of the NVH feedback you get from the Koni and others just isn't there on the Bilstein. Yet, the control is quite good.

Not a cheap option, but if you really want to be impressed with a shock/spring setup, have Fat Cat Motorsports build you a custom set. I hesitate to ever endorse anything on a forum, but these folks do it right. Yes, there are plenty of others but the approach is usually different. Check it out and see for yourself. You have to fill out a detailed technical application profile (including aero enhancements) and have a live interview/conversation to understand exactly what you want. Then you get to wait in queue for a couple of months before they can get to your order. I think you get the picture.

[Thecastle]

Originally Posted by rogerdiaz

Hi, what is the "install kit" you mention and do you have p/n for bumpstops? Were they OEM? I have 135,000 miles ZSP.

Technically no install kit was needed. However, since removing the struts/shocks on the car is required to replace the strut mounts you may as well replace them when you do the install. Otherwise you'll end up doing the labor 2x.

For me I purchased the tunermotor sports sturt/shock mount kit http://www.turnermotorsport.com/BMW-...nd-mounts.aspx

Though you can likely by the individual parts cheaper at pelican parts.

The dust covers and bump stops I purchased were http://www.pelicanparts.com/catalog/..._pg1.htm#item3

I purchased mine locally from a BMW parts distributor and use I purchased the OEM ones, however there really isn't a difference between oem and aftermarket. Keep in mind the bushings are different depending on if you had the factory sport suspension or the non-sport.

[PSEE]

I have an '09 335d that came with the BMW sport suspension with just over
75K on the clock. About 2K ago Turner installed Bilstein coil-overs. They
originally set them at 5F and 5R - the midpoint in the range. Shortly after,
I changed the settings to 4F and 6R, softening the front just a tad and stiffen-
ing up the rear.

These units are excellent!

I'd opted for H&R sport springs and Bilstein sport struts/shocks in all of my
BMWs prior to this. The coil-overs are a better solution, albeit a more pricey
one. All of the handling improvement with the plus of handling road irregular-
ities better than the previous sport setups.

[rulonger]

Originally Posted by DWR

But I have to say, on the road, Bilsteins are my favorite, by a good margin. I have put them on Volvos, Mercedes, BWMs, Porsches and the result is always the same. A smoothness that seems to be characteristic. Some of the NVH feedback you get from the Koni and others just isn't there on the Bilstein. Yet, the control is quite good.

I have been toying with a suspension refresh / upgrade. Lots of good spoken here for both Koni and Bilsteins.

So DWR, which Bilstein model would you recommend?

[Puerto Rican 335d]

Originally Posted by Pierre Louis

I've had great luck with Koni's and Bilstein's in the past, the Bilsteins for their gas pressure support of my old Suburban, raising the ride height a proper amount, while the Koni shocks helped tremendously with both ride and handling.

The FSD's on Axel's car were quite nice when I came to visit him and you could feel the difference from standard shocks for sure.

PL

Amigo when are you coming back down here , let me know AHEAD of time ok

[Pierre Louis]

Originally Posted by Puerto Rican 335d

Amigo when are you coming back down here , let me know AHEAD of time ok

Will do. You never know. Same with you - let me know.

[DWR]

Originally Posted by rulonger

I have been toying with a suspension refresh / upgrade. Lots of good spoken here for both Koni and Bilsteins.

So DWR, which Bilstein model would you recommend?

Originally Posted by DWR

I hesitate to ever endorse anything on a forum

To be fair, I know nothing about your vehicle or your expectations/wants/needs.