GrahamC

iTrader: (4)

After reading glowing reviews of how the MP4-12C rides over rough surfaces, yet remains taught enough on the race track, it got me wondering about the fancy dampers it uses and how long it'll be until similar technology filters to the aftermarket community.

Making a car better at the track has, for years, meant cars have been too stiff to enjoy on a backroad blast. I'm at the point where I no longer enjoy throwing my car down a B road anymore, which is a real shame.

So - how long until a realistically priced aftermarket Magnetorheological damper system will become available for popular cars? How much would you consider paying for such a system?

sjmarcy

Certain corvettes use similar shocks right now. The cheapest option might be to start from those bits and adapt / modify / develop.

Gotpsi?

iTrader: (5)

They are very expensive last time I checked like $1200 per shock, just the shock. Nothing else you would need would be included.

Joe Perez

iTrader: (8)

I've no idea how effective (or how quick-acting) they are, however the electromechanical bits for dynamically adjustable conventional shocks already exist: http://www.tein.com/products/edfc.html

JasonC SBB

Commercial MR shocks have a response time on the order of of 10-50 ms, which is enough time to do "skyhook" damping algorithms. i.e. the damping force is proportional to the velocity of the body motions wrt a virtual inertial reference as opposed to the relative velocity between the wheel and the body. Therefore the dampers will resist body motions but not resist wheel motions (bumps and dips).

The tein adjusters probably don't have the cycle life / durability to be able to dynamically adjust up to several times per second. So a stepper motor on the **** plus a control box with accelerometers, won't cut it.

As for the OP - MR shocks are still expensive (for now) and I don't know if Delphi would license out the patents to any small aftermarket company. The next complication is the software to provide optimal damping. The expertise probably doesn't exist outside of OEs, for now. Even if it did, the tuning is probably vehicle specific, and someone would have to figure out how to write a program and a manual for a user to tune it.

One parallel is the use of traction control. A well set up one will make a driver faster, and one company makes one - Racelogic. AFAIK only a handful of miatas have them. Why not? ..

JasonC SBB

BTW Koni's FSD is pretty cool. It starts out initially soft, and gets firmer after the shaft has kept moving for a certain amount of time. So rapid events (bumps), see soft damping, but driver inputs (roll etc), see firmer damping. A normal shock only presents a force that is solely a function of shaft speed.

The TireRack test of FSD shows better ride *and* handling than BMW factory and Koni yellow.

JasonC SBB

Koni's FSD now has comptition from Bilstein:
http://www.vehicledynamics-expo.com/.../brendecke.pdf

Joe Perez

iTrader: (8)

I wonder if we'll see either show up in an NA/NB fitment.

It certainly seems as though the DampMatic valve assembly and shaft could, in principle, be retrofitted into a conventional monotube shock body.

gospeed81

iTrader: (51)

I just want to know when we'll be able to adjust the damping/time response curves with MegaSquirt.

jeff_man

iTrader: (7)

ast 5100/5200 with 500/300 springs (or something like that) will be smoth street and bad *** track. Even my 5100 with 800/550 are not bad on the street with street tires.

JasonC SBB

Koni strangely doesn't have FSD available for many applications.
Some generations of BMW have it, and VW's.
Mazda3 but not the MS3. etc.