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View Full Version : Anyone using Ground Control's set-up?



erlrich
04-09-2003, 03:24 PM
Am in the process of installing the Ground Control coil-over kit, and ran into what I think could be a potential problem, and was wondering if anyone else has had this come up, and if so how you dealt with it:

The issue is that the upper spring perch is not attached in any way to the camber plate, and it appears there is the potential for the plate to lift off of the perch when the strut is fully extended (as would happen when jacking the car, or with the inner strut during hard cornering). There is a torrington bearing between the perch and camber plate, and I can envision this getting beat to death if it were to become dislodged (it's just sitting there on top of the perch), and causing all kinds of havoc. Even if it didn't move, I can't see how it would be a good thing to have the camber plate bouncing up and down on the spring perch. Is this normal for this type of set-up? Is there a way to restrict the stroke of the strut so this can't happen? This whole coil-over thing is new to me (my old Nova SS didn't need no stinking coil-overs), so forgive me if this is all elementary to those of you who have been doing this for forever.

As always, all help is greatly appreciated.

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Earl
ITA 240SX in process

handfulz28
04-09-2003, 03:53 PM
Don't sweat it, most if not all are like that.
I've seen some racers go to the extreme of using a very light "tender" spring, with just enough rate to keep the upper perch taught at full rebound. We on the other hand, use a zip-ty to keep the upper perch near the upper mount.
Chance are, if you're using stiff sway bars (Suspension Technique's seem to be the off-the-shelf bars of choice), you'll lift the inside wheel before the spring rebounds free.
Heck, I think I've gotten airborne over the bumps at Sebring, no problems there with the springs losing their way.
Oh yeah, when you jack the car up, the springs will be loose. Somehow they tend to find their way back to the right spot; sometimes they need a little "encouragement".

Michael

erlrich
04-14-2003, 11:27 AM
Thanks Michael - guess it was much ado about nothing. I just seemed to recall someone posting a topic a while back about the top perch on their car getting chewed up, but couldn't remember the specifics.

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Earl
ITA 240SX in process

MK
04-14-2003, 06:03 PM
Here's some tips for the GC set-up:

Get a second steel washer(same as the one between the bearing and perch) for the Torrington bearing and have the piece(one side is concave) that normally sits on top of the bearing surface ground the second washer's thickness. Put the second washer between the bearing and upper piece. That upper part is not hard enough and the bearing will wear into it(quick).

If you start getting into more than -2 degrees camber be sure that the upper spring perch isn't hitting your strut tower. You'll know when your turning the car the spring will bind and "thump-bang-thump" as it turns relative to the perch. Don't rely on the instruction's template for the cut-out in your towers, you'll probably have to cut more(along with the stainless ring that mounts under the tower's sheet metal. Consider welding studs to that ring so you don't have to reach under the fender to loosen and tighten the camber plate(for caster) If you're using just the kit and not ADS struts the top perch can also hit the bolt heads or nuts under that stainless ring.
Paint the top perch black so you can see if it's hitting. The best part is that since the hole in the top perch is oversize, it will cock when it's loaded, so if you look under the car when it's in the air, it may look like it won't hit, but when it's on the ground, or in a corner-SURPRISE!

You cannot eliminate that difference between strut shaft outer diameter and top hat inner diameter with a bushing. The radius ground under the camber plate is different than the radius of the spherical bearing in the plate. So you need the slop. Unfortunatly that allows the top perch to cock and the spring to eat some of the pretty threaded sleeves and the top hat to hit whatever you missed with a die grinder.

We've had the bearing jump out once, and I think it was more me not paying attention when letting the car down.

There was once a concern about the spherical bearing in the camber plate not holding up, but I think GC addressed that or it turned out to be installation error.

Have fun!
Kessler