Help, front ride height adjustment question
Chronic Tool Dropper
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From: Bend, Oregon
For the front shocks, the threaded ring that sits on the shock isn't very tall, something like 8 or maybe 10 *"threads" tall on its own IIRC. The outer adjusting collar is a lot longer. When adjusted to mid-range, the inner ring disappears inside the adjusting sleeve.
You can find the current location of the inner ring relative to the collar with a thin pocket machinist's scale. Or a piece of thin wire. Push it up underneath the collar and you'll find the lower end of the inner ring. Turn the collar a turn and you should be able to see that the distance changed. If no change the inner ring is turning, and you'll need to free it up.
Fair Warning Given: It's easily possible to turn the collar off the inner sleeve -- there are no safety stops. Going up it usually isn't an issue, as the collar will just sit on top of inner sleeve. Going down is a different story -- When you run out of threads, the collar will drop down free thanks to spring pressure. If you are doing this with weight on the tire, the car will fall a few inches, pinning your adjusting arm to the tire. Keep a close eye on the top of the collar for the threaded ring to be exposed as you adjust the collar down. Stop when you see the first *"thread" exposed. This will be inside the spring, so watch carefully.
* There's really only one "thread" on the sleeve, and a mating "thread" on the inside of the adjusting collar/ring. This one "thread" wraps around and around in a spiral. So talking about how many "threads" are exposed is really improper. Nevertheless, it's the easiest description for most to understand.
You can find the current location of the inner ring relative to the collar with a thin pocket machinist's scale. Or a piece of thin wire. Push it up underneath the collar and you'll find the lower end of the inner ring. Turn the collar a turn and you should be able to see that the distance changed. If no change the inner ring is turning, and you'll need to free it up.
Fair Warning Given: It's easily possible to turn the collar off the inner sleeve -- there are no safety stops. Going up it usually isn't an issue, as the collar will just sit on top of inner sleeve. Going down is a different story -- When you run out of threads, the collar will drop down free thanks to spring pressure. If you are doing this with weight on the tire, the car will fall a few inches, pinning your adjusting arm to the tire. Keep a close eye on the top of the collar for the threaded ring to be exposed as you adjust the collar down. Stop when you see the first *"thread" exposed. This will be inside the spring, so watch carefully.
* There's really only one "thread" on the sleeve, and a mating "thread" on the inside of the adjusting collar/ring. This one "thread" wraps around and around in a spiral. So talking about how many "threads" are exposed is really improper. Nevertheless, it's the easiest description for most to understand.
Racer
Joined: Sep 2015
Posts: 287
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From: Portland, OR
Old thread... Just want to confirm, before I break something, because I think my adjusters are set extremely low, so there's a risk of running it off the threads.
Is it right to raise the car and left to lower? Current height is 147mm LF and 149mm RF. No threads are visible on the collars.
Is it right to raise the car and left to lower? Current height is 147mm LF and 149mm RF. No threads are visible on the collars.
Racer
Joined: Sep 2015
Posts: 287
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From: Portland, OR
OK, so I turn it to the right, which pushes the nut up, which pushes the spring up and lifts the car? Just want to be clear on what's happening. Should I be concerned that there's no threads showing? Will threads appear underneath the nut before I run out of threads? Thanks.
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OK, so I turn it to the right, which pushes the nut up, which pushes the spring up and lifts the car? Just want to be clear on what's happening. Should I be concerned that there's no threads showing? Will threads appear underneath the nut before I run out of threads? Thanks.
Including a calculator on how MUCH to turn it, to get to a desired height.
Racer
Joined: Sep 2015
Posts: 287
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From: Portland, OR
Yeah, plugged my numbers into the spreadsheet. Looks like I need about 8 turns to the right. I'll do an equal amount on both sides so as not to change the corner balance. I see Dr. Bob says going up is pretty safe. Just wonder if I'll have 8 turns available since the threads aren't visible. Guess my springs could be old and sagging.
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Yeah, plugged my numbers into the spreadsheet. Looks like I need about 8 turns to the right. I'll do an equal amount on both sides so as not to change the corner balance. I see Dr. Bob says going up is pretty safe. Just wonder if I'll have 8 turns available since the threads aren't visible. Guess my springs could be old and sagging.
8 turns eh, thats pretty low..
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Chronic Tool Dropper
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On the Boges, the threaded ring that sits on the nubs on the bottom tube isn't really very tall. You can find out where the collar and the ring are relative to each other by using a thin mechanic's scale (ruler) poked up inside the bottom of the collar. You can see how far up it is, and how much adjustment you have available before the ring is exposed. On my '89 S4 with Eibachs in the front, it takes every bit of available adjustment to get the front height up to 170mm. The collar is sitting on the top threads of the ring. In this picture I just shot from behind the left upper control arm, I count eight (8) exposed turns of the ring under the collar. Going the other way, the spring perch hangs on the threaded sleeve as you lower the collar. It's not a good idea to do that, as there isn't much perch holding the car up.
The picture:
The picture:
Racer
Joined: Sep 2015
Posts: 287
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From: Portland, OR
OK, confirmed I have Boge shocks. Everything looks stock. Found a photo of the stock front sleeve, and it is very small, only about 11 threads. The nuts are about 24 threads, so it's clear why the threads aren't showing, and it does look like it is close to the bottom of the adjustment. I seem to recall the PO had some 18 or 19 inch wheels that he didn't sell with the car, so that makes sense (assuming he didn't care about suspension geometry).
I've got the car jacked up and gave both sides a couple of turns. Didn't take too much torque to get it started. I'd be surprised if it was more than about 40 ft lb. Now they turn smoothly with about half the effort. But I notice the droop in the suspension is not changing. Is it supposed to? Makes me suspect the sleeves are turning. But it seems odd that both sides would have the same issue. Thanks.
I've got the car jacked up and gave both sides a couple of turns. Didn't take too much torque to get it started. I'd be surprised if it was more than about 40 ft lb. Now they turn smoothly with about half the effort. But I notice the droop in the suspension is not changing. Is it supposed to? Makes me suspect the sleeves are turning. But it seems odd that both sides would have the same issue. Thanks.
Pro
Joined: Dec 2016
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From: SW Minnesota
With the car up on jacks, the suspension will fall to the lower limit. Adjusting the springs will not move the wheels lower.
Make the adjustments, lower the car, measure, and then put some miles on it.
Measure again.
Make the adjustments, lower the car, measure, and then put some miles on it.
Measure again.
Chronic Tool Dropper
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Make your adjustments after measuring the relative spacing between the threaded sleeve and the adjustment collars. In my picture you can see my red telltale mark on the collar, making it a little easier to count the turns. Follow the 'turns' guidance in Jeff's spreadsheet/calculator. Measure the delta between the parts before and after your adjustment to verify that the sleeve isn't turning on the shock tube. Where you see the sleeve sticking out the bottom of the collar in my picture, it normally sits up inside. Measure how much with your thin pocket scale stuck up in the gap from the bottom. If the spacing changes as you turn, you are golden. If it stays the same, plan on disassembling and then freeing up the two pieces so they will adjust. In extreme cases where we couldn't get the threads free, we've added some good used pieces from 928 International. Mark saves the best pieces from dry southwest-climate no-corrosion cars to sell, so these are a great option if yours are no longer serviceable.
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Joined: May 2004
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From: Philly PA
I should add you will not see any of the threads of the inner ring on Boge shocks when the suspension is set for normal ride height, using stock springs
Unless something else has been changed like a spring cut or some other thing has changed
Unless something else has been changed like a spring cut or some other thing has changed
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From: Boulder Creek, CA
Theres nothing useful to measure after you lower the car, only after miles driven.