New Koni 'Frequency Selective Damping' shockers released!

[pundit]

Koni have recently released a new shock absorber call the FSD (http://www.koni.com/FSD/) or Frequency Selective Damping.

The valving automatically adjusts depending on the frequency of road irregularities.
The greater the 'bumps per second' the softer the valving self-adjusts reducing harshness and preventing loss of traction which can occur when the suspension is over damped causing the wheels literally skip over the bumps.
As the rate of the 'bumps per second' decreases the valving increases the damping force resulting in tighter handling.

If they work as claimed they may put an end to those seeking the ride versus handling Holy Grail! :)

The only catch is whether they release a version to suit our E34's?

[BigKriss]

nice mate. no e34 shocks yet.

[genphreak]

They won't. Monroe have Select-a-trac's in Australia, I believe they have this feature and have an E34 fitment. Not sure what they are like though, they aren't a quality device from what little I know...

[pundit]

They won't. Monroe have Select-a-trac's in Australia, I believe they have this feature and have an E34 fitment. Not sure what they are like though, they aren't a quality device from what little I know...
I don't think I'd bother ever mentioning Monroe & Koni in the same sentence!
I think it's unlikely Koni will make FSD's for 10+ year old cars. Still, if the return exceeds the outlay, who knows? I'm even more inclined to keep my E34 for quite some time after I sat in a new 5 Series recently. The finish, especially anything plastic, seemed quite tacky compared to the E34. Now if I could just get 50% better fuel economy out of my M30 I'd probably keep it for 10 years!

[BigKriss]

I don't think I'd bother ever mentioning Monroe & Koni in the same sentence

Why do you get ****ing aussie's who put this **** across the back of their windscreen, most likely seen on a holden. This make me laugh. agreed. monroe does not give me any sence of confidence.

[genphreak]

Gabriel also have this feature, not sure if they include it on E34 versions. Its not that unusual these days (am sure there are others), but Gabriels are not exactly a class shock either...Economy from an M30? My ultimate would have to be a low-boost turbo setup on a nicely rebuilt motor w/ splitsecond MAF conversion. Ultimately, M30s are big-valved, old iron block (heavy) designs; they are reliable as hell and strong as Oxen, but economy is not exactly their forte... so pundit your point is a good one. :(

[pundit]

Gabriel also have this feature, not sure if they include it on E34 versions. Its not that unusual these days (am sure there are others), but Gabriels are not exactly a class shock either...Economy from an M30? My ultimate would have to be a low-boost turbo setup on a nicely rebuilt motor w/ splitsecond MAF conversion. Ultimately, M30s are big-valved, old iron block (heavy) designs; they are reliable as hell and strong as Oxen, but economy is not exactly their forte... so pundit your point is a good one. :(
Many manufacturers have what they refer to as auto adjusting shock absorbers. The difference being that the self adjusting mechanisms vary. Some progressively increase the damping as the shock compresses (like a variable rate spring). So on smooth roads the shocker can be fairly soft, but if the road is smooth a firm setting doesn't matter as there are no bumps to deal with and that's exactly when you want more dampening to improve cornering. The shocker won't stiffen up until it begins to compress due to body roll so you have already lost some cornering performance by the time the shocker begins to stiffen up.

Other types of auto adjusting shock absorbers increase the dampening based on compression velocity, the speed at which the shocker is compressed. But this still is not perfect. Sudden compression changes will cause the valving to increase dampening but more gradual compression changes will have less effect. Like turning into a corner on a smooth road that progressively tightens. If the rate of compression change is not fast enough the dampening won't increase much so body roll will be the result.

The Konis work on frequency. The higher the frequency, the softer the dampening, the lower the frequency (less bumps) the firmer the dampening.

BTW - Whoever named dampeners, shock absorbers was an idiot.
The Pommies (our British friends who can't play cricket for those who don't know what a Pommie is :p) generally refer to them correctly as dampeners.
The springs are the shock absorbers, and it's the dampeners that control or dampen the spring oscillations. - Sorry had to get that off my chest! :D

As for the M30?... well maybe in a few years I might pick up a 3.0 liter BMW diesel to replace the M30 in my E34.

Just check out this spec from the current 530TD diesel...

6 cylinders/24 valves
Capacity 2993cc (3 litres)
Max power - 272 BHP
Max Torque - 500nM @ 1750RPM
Economy - 42mpg (combined) or 6.7lt/100km
Acceleration - 0 to 60mph in 6.8 sec
Top Speed - 155mph


500nM of torque @ just 1750rpm AND 42mpg!!!!
I reckon it sounds pretty damn good! :)

[Anton CH.]

Body roll actually has nothing to do with shocks. The amount of body roll is determined mainly by spring rates and sways.

[pundit]

Body roll actually has nothing to do with shocks. The amount of body roll is determined mainly by spring rates and sways.
While in a perfect world we could pidgeon hole each suspension component into only performing its intended purpose and crossing into no other area, it's not possible with current conventional suspension design.

While the following maybe intended...

Springs should only absorb shocks.
Shock absorbers (dampeners) should only control spring oscillation.
Sway bars should only control body roll.

The reality is all the above will effect body roll.
Sways will also alter the total spring rate as they become loaded during cornering etc.

Shocks do effect body roll even though one could say that was not their intended purpose. I'm not suggesting this is correct, or necessarily desirable.
If the only concern is excess body roll, then by all means, change sway bars.

Many here look for lowered springs, which often require different dampeners.
We here many stories of how Bilsteins improved the handling on good roads but ruined the comfort. ;)

[Anton CH.]

Well don't forget that shocks play their biggest role in corner enter and exit. It's how quickly the body roll occurs. So perhaps that's why Bilteins appear to handle better.

I am really wondering how these shocks work. They are not saying much on their website.

P.S. Progressive springs were supposed to accomplish the same thing-ride comfort and great handling, however, I don't see too many manufactors utilizing this technology. And track guys prefer the linear springs in general.

[BigKriss]

Well don't forget that shocks play their biggest role in corner enter and exit. It's how quickly the body roll occurs. So perhaps that's why Bilteins appear to handle better.

I am really wondering how these shocks work. They are not saying much on their website.

P.S. Progressive springs were supposed to accomplish the same thing-ride comfort and great handling, however, I don't see too many manufactors utilizing this technology. And track guys prefer the linear springs in general.
h&r springs are progressive

[bahnstormer]

almost all street springs are progessive....

race springs are not...and they SUCK on streets, excel on race tracks tho =]