Anyone tried the new Koni FSD struts?
 

Has anyone heard of or had experience using the new Koni FSD struts? Edelbrock had similar system with their IAS shocks. Once I used the IAS shocks I installed them on everything I drove, They were extraordinary. I am quite interested in these new Konis and would like to hear thoughts. Thanks


KONI: shock absorbers kit containing front & rear shocks

I had some Koni FSDs installed on mom's 2001 VW Golf. The car was amazingly smooth over speed bumps, yet handled petty well. Not as good as high-end performance oriented shocks, but a good compromise for a street car where comfort and compliance over bumps is worth trading off for a bit less than the max performance.

For my 2001 box that I just upgraded to M030 springs, I opted for Koni sports rather than Koni FSD. Just because it's a Porsche, and I want it to feel more sporty. Don't mind feeling a little of the bumps. Still is not bad with the Konis sports. The FSDs also are not adjustable like the sports are (only the fronts are truly externally adjustable on the Boxster Koni sports - to adjust the rears requires they be removed).

The Konis (both FSD and sport) are both still a pretty new product for the 986 Boxster, having been out for less than 1 year. Maybe someone else here will have tried the Koni sports, and can report.

They are ok.
I prefer bilsteins with stock springs.
O o

I installed the Koni sports on my car about 5,000 miles ago and I really like them. Mine are set to the softest setting and are perfect for the street. Nice stuff ride but not so stiff speed bumps and rough patches are a big issue.

[QUOTE=jakeru;470614]I had some Koni FSDs installed on mom's 2001 VW Golf. The car was amazingly smooth over speed bumps, yet handled petty well. Not as good as high-end performance oriented shocks, but a good compromise for a street car where comfort and compliance over bumps is worth trading off for a bit less than the max performance.

For my 2001 box that I just upgraded to M030 springs, I opted for Koni sports rather than Koni FSD. Just because it's a Porsche, and I want it to feel more sporty. Don't mind feeling a little of the bumps. Still is not bad with the Konis sports. The FSDs also are not adjustable like the sports are (only the fronts are truly externally adjustable on the Boxster Koni sports - to adjust the rears requires they be removed).

Jakeru Thanks for the reply. My apologies for not responding. I somehow missed the reply in my own post!!:( I'm with you on the adjustable shocks. I've had several Adjustable Koni's and since they were a PITA to adjust they usually remained on the original setting.

Are you saying the FSDs are ok or the Sport?
Koni's have always been great shocks and for a lot of years were THE shock to own. Koni is pretty limited in their explanation of the technology behind the FSD shock but in my opinion is a mechanical version of PASM. Yes I know PASM uses a computer to control many more aspects of wheel and body control, but both use fluid control. I have attached an article which offers a little more info on IAS technology, and yes it is used in racing!

Inertia Active Suspension Technology

IME, just having one end of the car being adjustable can be a tremendously useful tuning aid if you ever autocross or otherwise want to dial in the handling characteristic (understeer/oversteer) to near perfection.

I think about Koni FSD as being an extremely digressive shock valving - more digressive than any other shock valving on the market.

Agreed! As far as I know they are the only shock offering the technology to our cars. This is the part I am curious about i.e. In a large impact when bypass opens and blows through the spring travel, what happens when/if it hits the bump stops? I do have experience with this tech offload and I thought they were amazing but what really set them apart was how they handled washboard. Instead of skittering around on top of the bumps they were very compliant and took it in stride.

I have some dyno plots of the rear 986 Koni sports. Not quite as digressive looking as I was hoping to see, but I'll bet they're going to work very nicely. Would be interesting to compare it against a 986 FSD shock dyno plot, if anyone could muster one of those.

(I had to return the first set of Koni sport rears for exchange, due to unbalanced compression valving left to right. Koni made good on it and sent me the new replacements along with individually tested dyno plots.)

I'm not really sure what you're asking about with the bump stops. But these 986 bump stops are rather long/tall and engage early, giving basically a progressive rate spring.

Dyno plots for suspension?...

I'm lost :(

Even in NASCAR!

Shock Absorber - Shock Dyno - Reading Shocks - Circle Track Magazine

Well I'll be damned. A shock dyno. In all the years I've had an interest in automobiles... that's a first. Does seem a bit of overkill for a road car, but hey, if I can optimize within my budget, why not? I'll hafta look for such "dyno" comparisons of suspension setups I'm interested in once the time comes to replace the factory pieces.

Interestingly, the "Bilstein Oval Track Technical Center" is eight miles up the road from me. Wonder if I can audit a class 'er two?

NASCAR!!!! These shocks were developed with the McLaren F1 racing team.

https://www.tirerack.com/images/pdf/koni_mclarenF1.pdf

I just installed them on my 996 with eibach springs and sways. The car is about an inch lower but feels almost the same as before as far as dynamics go. It's as if the struts are slightly softer than stock and the springs progressively firmer. If you want a better ride height, but want the car to ride essentially like stock then I would recommend them. There was no transformation of the car like in my boxster when I switched to biksteins and hr bars and springs. I hope that helped.

Thanks! All input is appreciated. What was your decision driver? I see these FSDs are highly thought of on the Renlist. Also your comments tend to mirror the Tire Rack test concerning the slalom, Where they initially thought the car too soft and comfy until they timed them and they outperformed the Sport on the soft setting. I think the explanation was the FSD maintained tire contact much better.

Here is the shock dyno plot for my two rear 986 Koni sports. (I believe set to minimum rebound setting.)
http://986forum.com/forums/uploads01...1452313809.jpg

The purpose of the dyno run (performed by Koni) was to verify that both sides matched before they sent my repalcements. This was the replacement set Koni shipped which I still need to install in the car. The set I initially got and returned were quite uneven in low speed compression damping (even without a shock dyno, it was blatantly obvious to me that one side compressed about 3x as fast as the other given an approximately equal force... which is definitely not the hot ticket as on konis only the rebound adjusts so you'd be stuck with screwed up shock valving and poor handling characteristics!)

I'd be interested to hear what the above plots looks like (in terms of the "kinked" shape, etc) for someone really into suspension tuning who is really up in interpreting these things. (Although comparing against similar Koni FSD plots for the 986 rear, if they could be obtained by anyone else somehow, would be very interesting to see!)

I take my suspension setup seriously as I have an interest in autocross racing and any serious competitor there knows the importance of good shocks. (In stock class, shocks are one of the few things that are allowed to be modified.) I trophied at SCCA Solo nationals a few years ago in a "lowly" VW. (But it was rocking custom-valved, double adjustable Konis front and rear.) I hate to say it but the lowly VW can still run circles around my 986 at lower speeds. (At higher speed, the aerodynamics of course favor the Boxster.) So I've got some more work to do on my fairly high-mileage 986 to bring it up to my performance expectations for what a Porsche should do. (The front suspension rebuild was already a huge improvement, but I'm really looking forward to getting the rear Koni spots on there.) For many years, I've admired watching Boxsters with the mesmerizing and amazingly neutral looking handling dynamics dodging autocross course cones at speed.

Jakeru looks like a very well matched set of shocks. I'm certainly no shock expert, those guys are magicians, anyone that can design a suspension for a stadium truck that can launch 20 feet in the air and land on level ground like a butterfly with sore feet really knows their stuff. What I do see from the chart is that these shocks are very linear. The compression is linear in the slow speed until the transition to high speed where it firms up just prior to valve pack opening and is divergent in the high speed circuit. I see what you mean by not being as divergent as one would expect. In fact I would have expected the initial response curve to be much steeper. These are definitely on the full soft setting based on the rebound slope (no knee). It would have been really useful if they had made a few plots with a couple adjustments to the firmness setting. Guess that's for the experts.

I have a damper plot for a standard S damper at 65k ish and an M030 at approx 105k ...

Can you post it? I have requested a Dyno sheet from Koni NA for the FSD shocks and will post it here for comparison if they come through. Thanks

I went the fsd route because the bilsteins and hr setup on the boxster was too stiff for my wife and lowered the the car too much. I also don't track my car so I was not interested in pss9 and the additional expense. I had Komi sports on my old 914 and had hoped they would be a good choice.

I appear to be a bit of a guinea pig on the 996 as most renlisters running fsd are 993s. My feelings are that the eibach and fsd combo is a little soft. But then again it still rides well and doesn't crash over rough roads. It certainly doesn't handle worse than stock, the ride height looks much better, and my wife still rides with me!

Thanks for that feedback. Sounds like what I'm looking for. :cheers:

Well Koni didn't come through with Dyno results. They did send the following. No clue what it means though..

Monty,
Thank you for contacting us here at KONI NA. Unfortunately, I do not have Force v. Velocity graphs readily available for each of the dampers offered. I can however provide the factory specs at which the shock are tested to for quality control.

Tested at .33m/sec (13in/sec)

Front FSD- 8745 1328
Compression – 350N
Rebound – 1350N

Rear FSD – 8745 1329
Compression – 900N
Rebound – 1650N

Sports
Front – 8741 1573sport
Compression – 500N
Rebound – 1250N

Rear – 8740 1574sport
Compression – 1050N
Rebound – 1550N




Mason O’Hara
Technical Sales Represenative
KONI - an ITT company

1961A International Way Hebron, KY 41048
(859) 586-4100, (859) 488-0324 mason.ohara@itt.com
KONI NA | Home www.koniracing.com www.konirv.com

These specs don't show how digressive the shocks are, but basically what I'm getting is that the Koni FSDs are lighter in compression (especially at front) and firmer in rebound than the sports are when set at full soft setting (which is where Koni measures their specs, as I understand it). If the sports were adjusted firmer, I expect their rebound rate would first match, and then exceed, the FSD's rebound damping.

The specs Koni provided for the rear sports match the dyno plots I posted for mine - look at the far right end of the graph (highest speed measured is where Koni checks their specs, apparently).

And that all makes sense. Since this test is at the high frequency 13ft/sec, this is where the valve on the FSD is wide open and providing the least resistance. This is what would be happening over say a speed bump. This allows the spring to compress while transferring the least amount of upward force/lift to the chassis. The info that is missing is what is the force at the low frequency setting? I think I read somewhere the FSD is actually stiffer than the Sport (full soft) in the low frequency travel.

Hi guys - new member.
I have just bought a bargain 123k mile 2002 2.7, looked after but obviously a little past its best. I am researching options for dampers.

I've had a quote for M030 at about £1100, I can get Koni sport or Koni FSD for about £550.

Currently I am not fussed about lowering the car - so replacing the shocks only could work. I would probably want to add in some Anti roll bars though.

Has anyone run the Koni sports (or FSD's) on standard springs, particularly older ones? Reccomended or not?

My thinking is a decent ride height and soft-ish springs, but with stiffer ARB's will give a good balance for driving on the tight bumpy roads we have here in the UK but not too roly-poly on the odd trackday.

Why not just buy Koni's package? Sports Dampners and Ebach springs?

I have seen some talk about this package but hadn't seen one for the 986 Boxsters, do you have a link? Would be a neat package.

I'm gonna leave your handle alone......:cool: As far as the Koni FSD's go they are designed specifically to use the stock springs on your car. They do have a set that comes with springs if desired.

Steved0x,
Just call them in Hebron, Ky. I was there for a tech session last week. Great Guys and real helpful.
859-586-4100

ditto the above - I've not seen a Koni supplied spring/damper package available (certainly not in the UK at least).

Ref the handle - don't ask!

I wasn't able to get anyone on the phone (it directed me to leave a message and then said the mailbox was full and hung up on me, I was trying the tech line, maybe should have tried sales :) ) But I emailed them and they got back immediately.

Koni confirmed that the FSD works with 986 Boxster springs, either M030 sport or "regular" (did not ask about ROW springs but they are popular in the UK so I imagine yes). It is compatible with the Eibach Pro kit springs for Boxster, which Eibach doesn't make anymore, so there is no kit from Koni for Boxster that includes springs. Eibach does still appear to make the Pro-kit springs for 996 2WD variants, and I think that is what Koni offers with their FSD+Springs kit for 996. They are listed as lowering the car 1" front and rear.

From time to time a set of the 986 Eibach pro-kit comes available for sale - there was one on here a while back, new in-box.

I have H&R springs on mine. Lowers about 1"

Seeing as this thread comes up top of Google when you search for "Boxster Koni FSD", I thought I'd add that in the end I went ahead and ordered them, in the post currently. I'llet you know how I get on once they are fitted.

Too funny! I pulled this up yesterday thinking about closing or at least adding to the thread I started, but felt I wanted a little more time to evaluate. I installed these FSDs ~1k ago. I just had the alignment done. Unfortunately a comparison to the stock system is limited due to my stock driver side shock was shot. Good news is all other suspension components were in good shape so no major changes there. What I can say is I am extremely happy with them. Broken pavement no longer jars the suspension, bumps and potholes are now soaked up and have a soft and "plush" feel. Turn entry is immediate and much firmer with hardly almost no body roll. Uneven pavement in the corner no longer unsettles the car, the failed front shock could have contributed to this though. Bottom line is if you're a dedicated racer and have to have your ski boots buckled so tight they hurt, then these are not for you. However if you want increased comfort and are tired of gritting your teeth when driving onto a bridge but don't want to give up any handling, then I wholeheartedly recommend these shocks. I am impressed so far.

edit: I have a close friend that has a 2001 S with 107k that is meticulous with maint. He has the Bilstein sports w/ HR springs. I have driven tis car multiple times. My feeling is the FSDs give up very little if any to the Sports handling wise but I feel are actually superior to the Sports on turn entry. Remember this is the low speed circuit where the FSDs have the firmer valving.

Details are: 98 base w/M030 sways front and rear. Michelin Pilot SS. Alignment specs: Front- Camber 0.3 deg, Caster 7.7, Toe 0.03 in. Rear- Camber -1.7 Toe 0.10 in

I put a set on my wife's 06 bmw wagon grocery getter. After a year and a half, one of the rears started pissing out fluid. Switched to Bilsteins and no problems after 3 years. YMMV

That's very reassuring to hear! I also have all new coffin arms, tuning forks, top mounts etc to go on at the same time so I'm expecting a dramatic change - it's currently feeling very worn out!

..........

I had replaced my rear upper control arms (tuning forks) several thousand miles ago, I did replace new Bump stops, bearing plates and boots. My lower control arms were good. To do the fronts I only removed the calipers, rotors and top strut mount. Rears I disconnected the control arms at the camber and toe adjustment points. As an FYI the paint on the strut body was so thick on the rear they would not slide into the hub carrier. On reassembly I loosely assembled the control arms then carefully jacked the hub carrier up onto the strut.
Will be interesting to hear your thoughts! Gives us older car owners the ability to have a similar effect to the expensive PASM on the later cars. I really like mine. Now if StevedOX would weigh in with the track perspective......:D

Seems QC and handling is a lost art nowadays. Hopefully I'll get better results on my Porsche golf cart. I opened a case with my FSDs when they arrived when the shaft was stuck completely through the original box! Somewhere between the Koni factory and the sellers warehouse they received some really special handling. The struts were well packed with expandable foam so it took a real blow to cause that damage. Of course I've watched my skis being tossed 15 feet at the airport, and that was right in front of me! So nothing surprises me any more. I did a very careful inspection with magnification, especially the shaft but found only a minor paint scratch, no dent, on the body of 1 where a spring perch made contact and rubbed. Based on the struts positions in the box I don't believe any contact was made to the polished surfaces but the seller agreed to cover if they fail.

Oh and when I put the Bilsteins on my BMW one had completely lost it's N2 charge right out of the box so seems no one is immune.

I have the bilstein shocks also and I must say that they are stiff but not uncomfortable. Handling is good on rough roads and ride is more controlled.

I feel like I have replied to this thread and my replies aren't showing up, so this post is a test. Yes I love them! Search for posts by me with the word "koni" in them to see my various thoughts, or maybe my posts to this thread will show up...