Bimmerfest - BMW Forums - View Single Post - Koni FSD Review (very lengthy)
View Single Post
Old 09-20-2012, 09:07 AM
GoForthFast GoForthFast is offline
Officially Welcomed to the 'Fest
Location: New York
Join Date: Jul 2004
Posts: 3,508
Mein Auto: '04 330Ci 6-speed
Posted my review probably five years or so ago, but probably not on this board. So apologies if you've seen it before, but for anyone who hasn't seen it before and values another opinion:

FSD thoughts and Axxis MM bonus panic test

My disclaimer is that these are all my own perceptions and might not be what you feel if you did this evaluation. I did pay close attention under various situations as you will see, but have logged only about three and a half hours of drive time so far. If things seem different down the road, I'll surely do a long term recap and report here.

I'm writing this to try to portray precisely what the FSD shock installation on my e46 feels like under various conditions. Not to just say "better ride/better handling", but to explain in detail where you will feel the changes. I want to get you as close to knowing what you'd be getting if you made this switch to decide if this is the setup for you. It's too large a commitment of money plus labor to leave to pure experimentation.
I have the 330Ci with sport suspension with staggered tire setup and manual transmission. I left the oem springs on the car. I might have gone with stiffer springs if I could have found some with no decrease in ride height, but I didn't want a lowered car for the current horrible road maintenance I find all around the USA.

At first it's a little disconcerting to drive down the road with my new FSD's because the suspension feels as if it has an added mush factor. I normally associate this with bad/isolated handling, but that just isn't so in this instance. All the normal feedback that keeps you thinking the suspension is tight and ready for business has turned into a soft ride that removes the 'harsh' factor. And that's one of the primary large differences, no more 'harsh'. The car still feels solidly connected to the road, but the wince-producing slap of small potholes, road patches, and banging of highway separators is greatly reduced. You get just enough isolation to yield the quality of ride improvement claimed by all.
But the surprise is that when pushed thru a normal corner, the car handles better than before, but seemingly with less stress. I found myself going faster with a more sure feeling of stability. When I thought about the event immediately after, I realized there is a softness added to taking corners at a higher speed with a more relaxed sense of control. I have to attribute this to the Koni's keeping better contact of the tires with the road while somehow delivering a smoother ride.
Long sweeping curves such as a large clover leaf highway entrance (taken hard) also reveal more. I think I was able to take my favorite much faster, but felt that the hunting requiring constant steering correction was gone. (I might have guessed that bad control arm bushings has been replaced with new ones had I not known what I installed) This translates to going faster, with a more stable feeling, and requiring less skill from me. The car does a better job. I was more relaxed at a higher level of performance. In retrospect, every time I do something with this increased capability, I think about why it feels strange, and the answer is always that it feels smoother at the limit. And that's weird.

Perhaps of a more subtle nature, I believe even the straight line tracking was affected. I felt as I was driving on a straight country road, the car didn't require as much constant minor correction to stay in my lane.

It's going to take some getting used to regarding perceiving a softer riding car as capable. But when the car is going fast and working hard there are no second thoughts. It will be interesting to see what my long term reactions are, but so far I think I like it all. No regrets. Very impressed.

Axxis MM brake pads (from Turner Motorsports)
Recently the question of these pads and cold stops came up and so I decided when I was out testing my Koni's that my pads had been completely broken in, enough to not have to baby them any longer.
A few times at about sixty mph, I gave the brakes just short of full panic stop pressure. I had never used them that severely before, and was astounded what g force this car is capable of with the large rotors, large soft tire patch, and quality pads. The first stop was completely cold and solidly as safe as you would ever need. I'm used to considering my e46 as a thing of beauty, but this stopping power is brutal. Split personality!

Update as of 9/12: all opinions still hold!
Reply With Quote