Need help with JIC coilovers...
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From: Studio City, CA
Theory arguments aside, with the 8k springs, my rear end did feel softer when I reduced the preload from 10 mm to 5 mm. Maybe it's just my imagination, but this seems to be accepted as the way things work.
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From: Laguna
Originally posted by cdelena
I have not measured the spring rate but I have observed that preloading them does do two things; it raises the ride height and reduces spring travel that is left. Since I want to do neither I only used enough load to hold the spring firmly. When I want to change ride height I change the length of the body.
I have not measured the spring rate but I have observed that preloading them does do two things; it raises the ride height and reduces spring travel that is left. Since I want to do neither I only used enough load to hold the spring firmly. When I want to change ride height I change the length of the body.
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Originally posted by grumpy
Why would preloading the springs change the spring rate (or stiffness)? Preloading the springs should just change the position of the damper while the car is at rest. It seems to me that the only reason to change the preload is to optimize damper travel.
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Joined: Oct 2000
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From: Redmond, WA
[QUOTE]Originally posted by cdelena
[B]
What exactly am I missing?
The spring is squeezed between the perch and the upper mount, constrained by the shock stroke. I don't see how you can do anything but reduce travel by preloading the spring as it shortens the distance that travel is possible. Granted, if you don
[B]
What exactly am I missing?
The spring is squeezed between the perch and the upper mount, constrained by the shock stroke. I don't see how you can do anything but reduce travel by preloading the spring as it shortens the distance that travel is possible. Granted, if you don
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Originally posted by RT
dude, we're not changing the stroke so that goes w/o saying that the stroke ("total travel") isn't altered .... please, the issue with lowering cars is always bump travel, not rebound so stay on the subject.
dude, we're not changing the stroke so that goes w/o saying that the stroke ("total travel") isn't altered .... please, the issue with lowering cars is always bump travel, not rebound so stay on the subject.
Granted I don't have much personal experience with this, but why wouldn't you want to preload the springs (or unload the springs) to keep the "at rest" position of the damper at about the middle of its stroke? Wouldn't that provide the best driving characteristics?
Joined: Oct 2000
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From: Redmond, WA
Rev, you are correct in that the system should never reach the point where the shock tops out. This is one of the assumptions of a properly setup system that I failed to officially list although I did somewhat address it with the comment that you don't want to ever "lift a leg" due to an inadequate amount of sag:
... your sine wave should never have any abrupt corners or flats (zero slope) at the top or bottom.
As I commented to gernby, when we lower cars we tend to worry about the reduction in bump travel since we are specifically reducing it when lowering perches (reducing preload) and in turn, we inadvertently, increasing rebound travel. So on most occasions, with stiffer springs (less preload) rebound travel is never the issue ........ unless you get that General Lee paint to stick to the convertible top
Originally posted by RT
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...........So the correct procedure for setting up the shock is to dial in as much preload as possible that allows you to achieve the desired ride height w/o violating the positive sag rules or the mfgs max preload that the piston rod joint can handle (also you don't want to ever lift a leg because of an inadequate amount of sag)................
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...........So the correct procedure for setting up the shock is to dial in as much preload as possible that allows you to achieve the desired ride height w/o violating the positive sag rules or the mfgs max preload that the piston rod joint can handle (also you don't want to ever lift a leg because of an inadequate amount of sag)................
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As I commented to gernby, when we lower cars we tend to worry about the reduction in bump travel since we are specifically reducing it when lowering perches (reducing preload) and in turn, we inadvertently, increasing rebound travel. So on most occasions, with stiffer springs (less preload) rebound travel is never the issue ........ unless you get that General Lee paint to stick to the convertible top