Need help with JIC coilovers...
#1
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I installed a set of JIC coilovers a few days ago, but I'm having some problems. The most obvious problem is that I can't lower my back end far enough. I bottomed out the threads for the lower collar and it's only lowered about 3/4-1" in the back. I want to lower it another 15-20 mm, but there's no room to with the lower collar. I moved the spring perch down a little (I had 9 mm of preload on the rear and changed that to 5 mm), but that didn't really help much. What's wrong here? These were supposed to let me lower the car .5"
-3" below stock.
Also, the ride doesn't have me too impressed yet. I've got the dampeners set to 10 clicks right now and that's still not all that firm. I was expecting the car to ride like a racecar with the dampeners turned up this far, but it doesn't ride all that much firmer than stock. In fact, it might just be my imagination, but the car actually seems to have more body roll now than it did with my stock shocks and HKS springs.
Anyway, don't get me wrong, I'm not trying to say the JIC's suck or anything like that - docofmind was really helpful with me and JIC is going to take a look at everything on monday afternoon, but right now I'm getting a little worried about whether this was the right choice for me or if I should have gone with something more aggressive (Buddy Club?).
I really don't have much money to spare these days, so hopefully I can get everything settled out properly - I can't afford to spend this much money on my suspension without getting some major gains from it.
-3" below stock.
Also, the ride doesn't have me too impressed yet. I've got the dampeners set to 10 clicks right now and that's still not all that firm. I was expecting the car to ride like a racecar with the dampeners turned up this far, but it doesn't ride all that much firmer than stock. In fact, it might just be my imagination, but the car actually seems to have more body roll now than it did with my stock shocks and HKS springs.
Anyway, don't get me wrong, I'm not trying to say the JIC's suck or anything like that - docofmind was really helpful with me and JIC is going to take a look at everything on monday afternoon, but right now I'm getting a little worried about whether this was the right choice for me or if I should have gone with something more aggressive (Buddy Club?).
I really don't have much money to spare these days, so hopefully I can get everything settled out properly - I can't afford to spend this much money on my suspension without getting some major gains from it.
#2
You shouldn't have any pre-load whatsoever. The spring should feel loose when the shock is out of the car. You need to lower or shorten the shock body by screwing the shock into the bottom mount more and then shortening the "clevis" on the very bottom. If you have a digital pic. post it and I'll tell you what to do.
#3
Don't understand the problem. Is the threaded body fully screwed into the bottom mount? My car is an inch lower with ~1.25 " between the locking rings and it seemed to me there was adjustment left. Preloading the springs is not recommended by JIC, so most of us have the perch adjusted to hold the spring tight but no more.. the preload may be raising the corner a quarter inch or so. BTW, the damping stiffens up better in the 13-15 range but in warm conditions it is never as stiff as competition units.
#4
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I preloaded the springs because I started to worry they wouldn't be stiff enough and I was right. JIC recommends running them without preload to keep the ride comfortable, but I don't think they're stiff enough, so I was hoping to stiffen it up with the preload.
Here is a link to my pictures from the install:
http://reverendsgarage.net/index.php?conte...es=1&gallery=36
Here is a picture of the dampener on the car lowered as far as it would go:
And here is a picture of that dampener off the car and disassembled to show the problem:
I think they need to use a shorter spring (180 mm instead of 200 mm), a shorter dampener, and a longer lower bracket to allow more range of adjustment...
Anyway, JIC will be looking at the car on monday, so hopefully they will be able to help me get this all straightened out.
Here is a link to my pictures from the install:
http://reverendsgarage.net/index.php?conte...es=1&gallery=36
Here is a picture of the dampener on the car lowered as far as it would go:
And here is a picture of that dampener off the car and disassembled to show the problem:
I think they need to use a shorter spring (180 mm instead of 200 mm), a shorter dampener, and a longer lower bracket to allow more range of adjustment...
Anyway, JIC will be looking at the car on monday, so hopefully they will be able to help me get this all straightened out.
#5
Those look sweet!
Rev, you can't change the spring rate w/ preload unless you have so much preload that the shock stroke is topped out with the full weight of the car on it (even in that case you're not really changing the "rate" but just creating a step in the load vs deflection curve) . Preloaded or not, the deflected length of the spring will be the same since it's carrying the same load either way (you shouldn't be experiencing either end of the shock stroke while driving).
The only concern I'd have is if the spring is loose enough to fall off the perch at full extension (which probably won't happen anyways unless you're jumping the streets of San Francisco). In that case you may consider using tender springs in series w/ the main spring to keep things tight at full droop.
Rev, you can't change the spring rate w/ preload unless you have so much preload that the shock stroke is topped out with the full weight of the car on it (even in that case you're not really changing the "rate" but just creating a step in the load vs deflection curve) . Preloaded or not, the deflected length of the spring will be the same since it's carrying the same load either way (you shouldn't be experiencing either end of the shock stroke while driving).
The only concern I'd have is if the spring is loose enough to fall off the perch at full extension (which probably won't happen anyways unless you're jumping the streets of San Francisco). In that case you may consider using tender springs in series w/ the main spring to keep things tight at full droop.
#6
Just looking at the pic I would guess that you have about .9 inch between the lower locking rings. On my car I think that would translate to the rear being 1.7 inches lower than stock (w/ no spring perload which will raise the car). The stock height spec shows the fender arch 26.6 inches from the road surface. You are right, you won't get as much range as you thought, but I think you already have lowered more than you think.
#7
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Originally posted by cdelena
Just looking at the pic I would guess that you have about .9 inch between the lower locking rings. On my car I think that would translate to the rear being 1.7 inches lower than stock (w/ no spring perload which will raise the car). The stock height spec shows the fender arch 26.6 inches from the road surface. You are right, you won't get as much range as you thought, but I think you already have lowered more than you think.
Just looking at the pic I would guess that you have about .9 inch between the lower locking rings. On my car I think that would translate to the rear being 1.7 inches lower than stock (w/ no spring perload which will raise the car). The stock height spec shows the fender arch 26.6 inches from the road surface. You are right, you won't get as much range as you thought, but I think you already have lowered more than you think.