Quote:
Originally Posted by ddub
Critically damped is when the spring settles to equilibrium position the fastest, without overshoot. Critically damped is inbetween under and overdamped, pretty much the best setting for a spring and damper(maybe not for comfort). For underdamped, zeta<1, crit zeta=1, overdamped zeta>1. Check this link out: http://en.wikipedia.org/wiki/Damping
also here: http://cat.sckans.edu/physics/shm.htm
If I were to get softer springs, they would have more of a chance of being overdamped. The softest setting may work if I try this. It would cost $120 for the different springs and $80 for alignment. so the most I would lose is $200. Plus I would raise the car up for handleing purposes. The other choice is to get a completly different setup, so maybe this is worth a try. |
I'm not attacking, you are the one who posted asking for input.
I have just been asking questions, sometimes without answers and offering options and explanations.
Hopefully this one will make sense.
Critical damping setting is not an automotive term, and this is not a simple system. Automotive dampers typically have at minimum different high and low speed damping for each direction of motion and may or may not be linear. Many automotive springs are also not simple as they are one or more way progressive and may or may not have helper springs that further complicate things. And we won't get into the overall vehicle dynamics related to weight transfer and such which also impact damper design.
At most, your coilovers have one knob that affects anywhere from one to all four of the above damping rates, but most likely 1-2, most likely high speed rebound, and maybe high speed bump.
Unless you have spent a fortune, your 18s and larger rubber have added upwards of 20-40# of unsprung weight and as I said, added I am guessing, 100# of basically undamped spring rate in the sidewalls of the tires.
Your softer springs and stock dampers effectively insulated you from those.
The stiffer springs and performance oriented dampers likely have significantly lower tolerance for low speed motion and thus on the road, they feel bouncy as the tire sidewall is transfering significantly more force than stock. Due to the low speed damping, changing springs is unlikely to have a significant impact on perceived ride quality.
We have had a bunch of people had and then dumped their 18s and others dumped their coilovers or bought a daily driver due to unacceptable street ride quality. The rest of the coilover owners understand that bouncy on the street is one of the prices you pay for a performance suspension. Harmonics from trucks and such are the real problem, and there just isn't much of a way around them and still have a setup that is anywhere near optimal under performance driving conditions.
This is why lowering springs are often the best option for a primarily street driven car where the objective is looks, not performance.