[Drivaar]

I've been asking a lot of questions in the past few weeks about Koni FSDs, and recently I got them installed. So here's my review...

Basically, I can't imagine any better scenario than this:

+ Smoother ride than stock sport shocks on bumps and uneven roads
+ Firmer, more responsive, flatter ride for cornering
+ $650 for 4 shocks (vs. ~1,000 for stock sport shocks if I calculated right)
+ Minimal dive when braking
+ Minimal squat when accelerating

It really is as advertised, and I couldn't quite believe it. I've driven it on some terrible freeways, and all bumps, even severe ones, are much less intrusive now.

And then when you take a corner, the car is so level and responsive, it's stunning. Same thing with quick lane changes or avoidance maneuvers... the car's handling is just very sharp now while being more comfortable!

I am very very impressed. The only question I have about the Koni FSDs is whether they'll be prone to failure, since they are a little more complex than standard shocks. But Koni warrants them for their lifetime as long as you own your car, so I guess I don't need to worry about that.

I guess they have a good patent on the tech, because it seems weird that every car manufacturer is basically directly trading off ride quality vs. handling. As someone else had posted about the FSDs, these are the shocks that should come standard for a luxury sport sedan.

Bottom line: If you want to make the stock sport suspension strictly better, Koni FSDs are really the no-brainer choice if you have $650 + about $300 for install to spare.

I hope this helps anyone who's thinking about getting them. Just go get them!

And thank you so much to everyone who answered my many questions along the way!

[cdgatti]

Congratulations! This is a great example of how this community helps each other, you researched and made your choice and it turned out excellent. What car did you put these on and did it result in any kind of height adjustment? Do you feel any of the strange sensations that people report regarding the FSD's?

Regarding the KONI technology, I too wondered the same thing if it is really that much better, why isn't everyone using it at least on their luxury/sport models. Maybe it is Koni's patent position, but why don't the oem's use Konis, maybe cost? All that said, I did read somewhere that Mercedes must use a similar technology because some of their cars exhibit the same type of character as the FSD's.

[HighlandPete]

I've been using Koni FSDs on my E91 touring (wagon) for over four years the first to fit the FSD on the E91, in the UK. I'm on standard suspension and other than the FSD dampers (shocks) have left the car suspension OEM. No negative issues whatsoever, and I use some very poor roads. Same ride height and no fitting issues.

I did the research and the specification was exactly what I was after, was the best move I could have made to get a decent ride, on poor roads. They do what is said in the blurb. Improved primary and secondary ride quality.

As to other car makers using the same or similar principle, Mercedes do, on their standard agility control suspension (not the active system) as in the C-Class. They use a similar damper, hence why Mercedes have improved the handling while retaining ride quality on late models. I tried a C-Class with the selective damper fitted and it had a very similar feel to my car, with FSDs fitted, same sort of primary and secondary ride feel.

Koni: FSD



Mercedes: Selective Damper



HighlandPete

[Drivaar]

cdgatti: totally agree! The community was very helpful, and that makes me want to do a good write-up to share that info so other people can benefit.

It reminds me of many years ago when I was trying to decide whether to get sport suspension with my E46, worried about ride quality. It's another easy choice once you've felt it and know it's not a big problem. Koni FSDs are the same way, IMHO.

Ride height seems almost exactly the same. Honestly I don't care a whole lot about that, though I understand why some people want it lower. I save the lowest cars for my drawings, but in real life, I value the comfort so much more. Also depends on the roads each person drives on.

Given the right conditions, I'm sure there will be some oddness with FSDs. Possibly a certain frequency of bumps, or a certain variation in frequency of bumps. But that would be some tiny patch of road in the world, whereas the rest of the time they are great.

I will be taking them out for a longer drive soon, and will report back when I do. Also can't wait to take them to a certain deserted test area that I use, to see how they do under pressure.

Highland Pete: Thanks for the info. Good to know they last! The warranty also gives me peace of mind. Hopefully they will honor it if the time comes.

[HighlandPete]

Just a further thought or two.

I'm running 17" wheels. I bought a second wheel set and fitted non run-flats to them, (Goodyear F1 GS-D3) before fitting the FSDs, and found the car was improved for secondary ride. But it showed up the standard damping as too soft over sections of road where a good damper will absorb the shock in a single thump, the OEM damper (even at 9k miles use) would be like a "one and a half" type thump out. The FSD sorted this, but trying the RFT wheel set, I had major improvements, but the RFTs were still giving issues to steering, grip, etc., so back to the non run-flat wheel set. I've since replaced the Goodyear with a Falken 452, (great results here in the UK with Falken on the 3-series) and the car is even better in road feel. The Falken in 17" sizing, along with the Koni FSD seems to have hit the spot, as it were, suspension harmonics are much improved and makes the car feel much more mature in driving feel. So much so, trying other BMW models (looking to replace the E91), I'm even more disappointed with the current suspension dynamics.

HighlandPete