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PlatES300
08-02-2010, 05:58 PM
So I'm having some trouble with my new coilovers and I need some info. My rear spring rates are 3k and I'm thinking its a bit too soft. I've been messing with the dampers from full soft to full stiff and it still doesn't solve the bouncing problem. My question is, if I change out to a stiffer spring (5k), would it help the problem any? Thanks in advance for the help.

icemanimports
08-03-2010, 04:35 AM
does your set up have an adjuster at mount? if so did you use this to adjust your height? it should be washy not bouncy with a 3kg spring. typically i run 7kg rear on my 2000 SI. if you used the spring adjusters, you changed the preload of the spring which effectively raises the spring rate.

PlatES300
08-03-2010, 05:14 PM
does your set up have an adjuster at mount? if so did you use this to adjust your height? it should be washy not bouncy with a 3kg spring. typically i run 7kg rear on my 2000 SI. if you used the spring adjusters, you changed the preload of the spring which effectively raises the spring rate.

sorry but I was using the wrong term. it's exactly what you are saying, washy. I did not preload the spring - I lowered the car using the lower bracket, that way suspension still has full travel. I think I have it figured out. I found another member running coilovers as well and he said I need to change out the rears to at least 6k and the fronts to 9k.

icemanimports
08-04-2010, 10:11 AM
on my prelude i ran 8kg out back and 8kg up front, set my damping to hard as fak in the back and medium up front, IN AUTO-X it swung around corners like a FR car. street ride was crap though.

mikespeed95
08-15-2010, 04:01 PM
Information like what kind of vehicle, what mods to vehicle, what coilovers, etc etc etc really help situations like this.

Spring rates on cars really aren't comparable to one another due to things like...physics.

ebellis
08-15-2010, 07:12 PM
^+1

Spring rate is a ratio used to measure how resistant a spring is to being compressed or expanded during the spring's deflection. The magnitude of the spring force increases as deflection increases according to Hooke's Law. Briefly, this can be stated as

F= -kx

where

F is the force the spring exerts
k is the spring rate of the spring.
x is the displacement from equilibrium length i.e. the length at which the spring is neither compressed or stretched.
Spring rate is confined to a narrow interval by the weight of the vehicle,load the vehicle will carry, and to a lesser extent by suspension geometry and performance desires.

Spring rates typically have units of N/mm (or lbf/in). An example of a linear spring rate is 500 lbf/in. For every inch the spring is compressed, it exerts 500 lbf. A non-linear spring rate is one for which the relation between the spring's compression and the force exerted cannot be fitted adequately to a linear model. For example, the first inch exerts 500 lbf force, the second inch exerts an additional 550 lbf (for a total of 1050 lbf), the third inch exerts another 600 lbf (for a total of 1650 lbf). In contrast a 500 lbf/in linear spring compressed to 3 inches will only exert 1500 lbf.

PlatES300
08-15-2010, 08:27 PM
BC coilovers for an ES300. Car weighs roughly 3600 lbs, weight distribution on it is about 65/35. And coilovers are the only suspension mods I have for the car.

mikespeed95
08-15-2010, 09:03 PM
Thats the same as the camry right?

I'm not an expert on camry suspensions, but I'm sure someone wanting to look cool on the internet will chime in and claim to be a Camry road racing exp4rt, buuut your best bet is to try to contact BC. They normally know what they are doing as they are the actual owners of the facility that most overseas coilovers get made at, so they get to see what everyone else is/isn't doing quite well. If its bouncing, it could just be a poorly valved shock.

ebellis
08-15-2010, 09:34 PM
also try looking around at what other people are running on es300's, before buying my BC coilover w/ custom spring rate (10k on all 4) i checked around to see what others were running and talked to the guy who was selling them to me, because he uses his car for the track even though it is much lighter he was running higher spring rates. I ended up only going 1-2k above the BC standard for my car

PlatES300
08-16-2010, 08:07 AM
also try looking around at what other people are running on es300's, before buying my BC coilover w/ custom spring rate (10k on all 4) i checked around to see what others were running and talked to the guy who was selling them to me, because he uses his car for the track even though it is much lighter he was running higher spring rates. I ended up only going 1-2k above the BC standard for my car

Wish I had the luxury because I don't know of anyone that is running BC on their ES or Camry. I ended up getting a stiffer spring for the rear. OTS rates were 6/4 and I went with 7/5. Got the 5k springs yesterday so I gotta wait to install this week and see how it rides.

ebellis
08-16-2010, 10:59 PM
^ doesn't need to be same brand coilovers, vehicle weight is still the same, just compare spring rates with other es's

xanavi_D
08-17-2010, 06:18 PM
3k is real soft for something so heavy, the valving on the coilovers may be shitty as well