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Old 11-11-2010, 10:15 AM   #21
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Here is your fail:
You're screwed from the start on travel considering you have a 350lb spring, I'm running 500lb in the rear:
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Front mounted on the car:

Rear's have 1.5" before contacting the bump-stop, which means you have less travel with yours off the car than I have on the car. What is the ratio again for wheel movement/shock compression?

You need to raise the ride height significantly. I bet you're on the bump-stops at rest.
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Old 11-11-2010, 10:18 AM   #22
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I'm still going with coil bind. but everyone can ignore me.
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Old 11-11-2010, 11:09 AM   #23
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here's the proper way to set up an adjustable body shock for maximum BUMP travel for posterity:


1. jack up car and put on jackstands (rear at least)
2. pull the sway bar from at least one side
3. remove a shock and remove its spring. reassemble it normally just without the spring
4. shorten the shock body to the minimum but dont lock the collar.
5. install the wheel on that side
6. jack up the suspension arm on that side slowly and see what contacts first: tire or bumpstop or something else
7. lower the suspension arm and lengthen/shorten the shock until the arm jacks up with the shock hitting the bumpstop and the tire clearing everything by 1" (you should be able to reach your hand around and feel)
8. lock the collar for the shock length adjustment down.
9. reinstall the spring and the full coilover and then repeat on the other side of the car (or measure the shock body length and transfer it.

10. then once the shocks are all installed and happy, jack the suspension arm again and roughly set your ride height by turning THE SPRING PRELOAD COLLAR.

11. match the other side
12. lower and verify height. repeat til satisfied. don't touch the shock body length.

now you can ride super low without rubbing yourself the wrong way.
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Old 11-11-2010, 11:36 AM   #24
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Quote:
Originally Posted by greeenteeee View Post
chricto, would you mind measuring the shock shaft length (the chrome piece at full extension to the top threaded portion of the shock) as well as the shock body length (usually threaded and black... since you are all the way down into the lower cup/bracket, you can get an idea without removing the shock at all). A rough estimate is all I am curious of.
That pic was from them fresh out of the box. I didn't mess with anything until after the picture was taken. I'll get a measurement tonight when I put the car up on jack stands.

Quote:
Originally Posted by SignOfZeta View Post

OP, the reason you are hitting the stops is because, if that's your car in the sig, your **** is way too low. Preload is meaningless since once you put the weight on the car its completely overcome. The issue is ride height. Granted, they are kind of the same thing since the only thing you can do to adjust either without changing springs is by moving the lower perch, but conceptually pre-load only matters when the suspension is at full droop. 100lbs of preload, 200lbs or preload...it disappears once you put 500lbs of car on it.

To ride that low and still have travel, you'll need shorter shocks. If it weren't for those crazy upper mounts you'd be on the stops at rest. Actually, you might be on them at rest even with those mounts.

Raise the car and have actual functioning suspension, or lower it and look cool. Your choice.
As posted by others, the lower mount is like a threaded sleeve, so the ride height adjustment is completely independent from shaft travel. The lower mount can be removed completely, which has no bearing on actual travel. Also, I "slammed" the car to see how low it could go and to shoot some photos. Here is my current ride height.

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Quote:
Originally Posted by Braineack View Post
I'm willing to bet with those rear mounts, that you're coil binding and not close to hitting the bumps.
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Originally Posted by Braineack View Post
I'm still going with coil bind. but everyone can ignore me.
I think you might be on to something, here. I had to put the donut on a few weeks back after running over a nail. With the donut in the front, I was bottoming out the suspension even more. I checked the spring on that side and it was compressed almost completely. When I got my normal wheel back on, it went back to "normal". If it is coil bind, will longer springs help, or do I need stiffer springs because these coilovers just have short travel? Also, can you explain to me how the top hats could be causing this problem? I don't understand that in the least.

I'll snap some more pictures tonight to help answer some of the other questions that have been asked. Thanks for all the help.
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Old 11-11-2010, 11:51 AM   #25
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Quote:
Originally Posted by Braineack View Post
I'm still going with coil bind. but everyone can ignore me.
I think he'll run out of shaft travel before bind...but a chewing gum (or plasticine) will tell him if its coil bind.
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Old 11-11-2010, 12:10 PM   #26
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I think he'll run out of shaft travel before bind...but a chewing gum (or plasticine) will tell him if its coil bind.
Noted. I'll test this and zip tie the piston shaft to see what is actually happening.
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Old 11-11-2010, 12:19 PM   #27
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I had this issue with 8" 250# rear springs on my konis.



In this picture I have jacked up my control arm as far as I can go...you can see bind is just about to happen. The lower line is the top of my shock body. the upper line is the level when the spring rests, and my bump stop just barely would stick out lower than that plane. My bump is about 2" long...so think about that: I had TOO much travel. About 2" too much before I would just hit the bump, let alone the extra 1" or so before it's compressed.

with the ISC racing top hat, i still had of shock travel 2" before I would even touch my bump stop before I was coil binding.

the problem was since I was given all the extra travel due to the mount my car sat up too high to take advanced before i ran out of spring travel. I had to space the bump stop down about 2" and then I had to lower the perch in which the sleeve rested to prevent it, and also lower my ride height. Basically everything you can do to limit shock travel.

I ultimately got rid of the isc top hats, sit at the same height in the rear 12.5", and have zero issues on the same springs and bumps. Ride feels great in the rear.
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Old 11-11-2010, 02:17 PM   #28
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OK, some new **** has come to light.

I didn't notice these shocks had adjustable bodies. That's good...to a point, of course. I extreme cases the lack of droop they can cause has its own problems.

See the picture of his current ride height...that's in the same ball park as my NA (hard to tell with the different bodies) and I only have 200s in the rear, so I don't think spring rate is a problem in itself.

Read y8s's post. Its important because the more stuff you can adjust on a suspension the more mistakes you can make. 200 springs aren't a problem on my set-up, but if someone has their stuff adjusted to the point where there is so much travel that the coil binds before the bump stop is even compressed...that might be where you're at. Braineack might be right about the coil bind.
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Old 11-11-2010, 02:24 PM   #29
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yep.... so lengthen those bodies!!!!


after you do the zie tie test and say im correct of course...otherwise youll make it worse
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Old 11-11-2010, 05:45 PM   #30
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Quote:
Originally Posted by y8s View Post
here's the proper way to set up an adjustable body shock for maximum BUMP travel for posterity:
I've heard of this but never done it myself (lazy to install w/o spring and re-do). I left it at 0 pre-load at full droop. That method though, potentially uses up shock travel no? Say there is 1" gap between spring and perch to get the desired height, yet the bump travel is maximized via bumpstop so bumpstop bottoms before tire does...

The zipties should say if he is slamming into the bumpstops, and if it's coil-bind, he would probably see markings on the spring

As for coil-bind, I found this somewhere and it might be helpful to calculate coil-bind.



Unfortunately it won't have any info on Braineak's 250lbs/in springs but could give a clue on what rates and lengths will cause coil-bind and when. The OP's 6kg/mm is 336 lbs/in.
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Old 11-11-2010, 07:10 PM   #31
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Quote:
Originally Posted by greeenteeee View Post
That method though, potentially uses up shock travel no?
it shouldn't. you may not be fully extending the droop, but that's hard to do without really long, soft springs (or helpers) anyway.
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Old 11-11-2010, 07:18 PM   #32
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Quote:
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it shouldn't. you may not be fully extending the droop, but that's hard to do without really long, soft springs (or helpers) anyway.
How can I not be fully extending the droop? Doing it your method so that the shock bottoms out before the tire means the shock will be shortened than what I have now, since I do not bottom out at all, given my current ride height, spring rate and tire compound (180 TW RE11).

What helpers do, is use up the extra space, say that aforementioned 1" for which the helper is used. The helper is a dead spring, meant to keep the spring seated and it is using 1" of shock travel before the main coil is doing anything. What am I missing here so that it doesn't use up (waste) shock travel in your method?
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Old 11-11-2010, 08:20 PM   #33
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Originally Posted by chricto View Post
Noted. I'll test this and zip tie the piston shaft to see what is actually happening.
I don't think you need to check the shaft for bump stop travel, the stops are probably compressing at rest.
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Old 11-11-2010, 08:29 PM   #34
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I don't think you need to check the shaft for bump stop travel, the stops are probably compressing at rest.

have you even looked at his rear mounts?!
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Old 11-11-2010, 08:37 PM   #35
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his rear mounts have extended damper travel, the damper can travel up into rear mount a couple of inches before it even thinks about running into the bumpstop. Coil bind is going to occur long before the bumpstops compress on that setup.
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Old 11-11-2010, 10:53 PM   #36
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Quote:
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How can I not be fully extending the droop? Doing it your method so that the shock bottoms out before the tire means the shock will be shortened than what I have now, since I do not bottom out at all, given my current ride height, spring rate and tire compound (180 TW RE11).

What helpers do, is use up the extra space, say that aforementioned 1" for which the helper is used. The helper is a dead spring, meant to keep the spring seated and it is using 1" of shock travel before the main coil is doing anything. What am I missing here so that it doesn't use up (waste) shock travel in your method?
The helper spring just moves the main spring down by the compressed solid height of the helper and spacer. A few turns of the collar and you're back where you started.

Meanwhile...

If you're not bottoming out and you're not rubbing... then your shocks are either adjusted perfectly or too short (giving up droop travel). All the adjustment method I put up there does is prevent you from cutting up your tire while maximizing the upward movement of the suspension (bump travel).

"Too short" could simply mean your suspension doesn't compress enough to hit the bumpstop or the tire. A zip tie will tell you in one lap.
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Old 11-12-2010, 09:38 AM   #37
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I dont understand the "zip tie" - does it go on your damper rod above the bumpstop and move up as the suspension compresses so that you can tell if you have maxed out your suspension travel (by finding if the zip tie has moved up to the upper mount after a lap or two)?
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Old 11-12-2010, 09:51 AM   #38
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Below the bump on the shaft to determine the spot where the shock body pushes it. If he's coil binding, the zip tie will end up below the bumpstop, with a gap between. If he's hitting the bump it will be snug up against it.


here's the problem I had with ISC racing tophats (similar to the design he's using on his Stance).



konis have short bodies. with the car's weight, the 8" springs compress down to 5.5". So when I'm sitting at a ride height of 12.5" in the rear, you can also see there's a huge amount of shock travel you can compress.

Look at Hustlers picture of his rear shock. He has maybe 1.5" before he starts squeezing the bump, however, he has a lot more space between his coils (due to rates). If you look at my picture, I have about 3" of shock travel before the shock body is flush with the mount, hit the bumps, then there's a another 1" of travel beyond that point up into the mount...and I have maybe an 1" of total spring travel. coil bind city.

Notice my perches? I had to move to the lowest perch. With all things equal, the helped position the shock about .75" closer to the bump...still to no avail. And raising the ride height makes it worse, so if I kept those mounts, the only way to fight coil bind would be to ride at 11" or so in the rear.

someone needs to get up under his car and figure out whats hitting first, then we can really help.

Last edited by Braineack; 11-12-2010 at 10:09 AM.
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Old 11-12-2010, 11:25 AM   #39
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Quote:
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have you even looked at his rear mounts?!
Will the shock body fit inside the uppoer mount? I bet it won't, just like my rear FM mounts that don't fit into the mount making me double-up on bump stops. My rear's are Swift springs which are usually a smaller diameter too.
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Old 11-12-2010, 11:29 AM   #40
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i dunno. all i know is short shock bodies plus mounts like that = fail.
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