||01-21-2013 09:23 AM
cheap coilovers will have crappy dampers. its just math. just think about it. assuming your setup cost around $1200, `800 of that is for all the hardware, springs, camber plates and such. That leaves 400 on dampers, or 100 per corner. thats less than mores OE replacement units, so how can they be expected to be any better or more sophisticated. most of the people who give cheap coils good reviews are people who dont care about ride and/or dont know what a good coilover is supposed to fee like. And dont expect the dampening adjustments to be linear, accurate or equal between corners either. Its gonna be pure luck if you can find the settings that make you happy.
Let me make this as clear as I possibly can: THE ADJUSTERS ON YOUR SHOCKS ALMOST CERTAINLY DO NOT DO WHAT YOU THINK THEY DO. Unless you have something high-end, like a Penske, and you've taken the time to clock the adjuster window on the shock dyno, the knobs on your shocks cannot be trusted to work. Most shocks of the same model DO NOT match each other on the same adjuster setting, and each click DOES NOT make the same change in force. Most shocks make very large changes per click near the "full hard" setting and make very little to no change near the "full soft" setting.
Despite this easily verifiable fact, the Cult of the Adjustable Shock certainly has its adherents.
Consider the following:
Happy Fun Fact: Formula One cars use non-adjustable shocks. They get away with this by running the car on a seven-post shaker rig that plays back suspension movements recorded previously on that track, using the data the collect on the rig to tune the shocks, and once the shocks are tuned, those are the shock forces they use at the race. Once they're right, they're right.
- Shocks produce forces on a curve, depending on the piston velocity. There exists an "ideal curve" that is the force curve the shock should provide. But the actual curve the shock produces is something different.
- As you tune the shock, what you are doing is bringing the actual produced shock force curve closer to the ideal curve - and this has to be done over the entire range of the shock's possible velocities. It is entirely possible to have the shock match the ideal curve well in some places, but not well in others (this is the norm, in fact).
- As a shock is a reciprocating device (ie, it moves back and forth, not around in cycles) it spends most of its time at slower speeds, as it must slow down and stop before it can change direction. This means that improvements (by which I mean better matches between the "actual" curve and the "ideal" curve) at the slow speed part of the shock curve will pay bigger dividends than at the higher end, because the shock spends more of its time in the slow speeds than the high speeds. (There's a way to exploit this for tuning purposes and I'll get to that later)
- Once a shock is matched to the "ideal" curve, it is correct for the entire speed range of inputs - meaning that it never has to be adjusted.
OK, so what if they aren't right? Wouldn't it be good to have an adjuster for tuning purposes?
Well, yeah, it would be - if the adjuster worked as advertised. In my experience on my shock dyno, most adjusters DO NOT work the way you think they do - in some cases, horrendously. It's like having a blind man adjust the focus on your camera. What's the point?
And that's if the left and right shocks on the same end of the car act the same - when in reality, they almost certainly do not (unless you've taken the time to match them)
from - http://farnorthracing.com/autocross_secrets6.html