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Will replacing the shocks mess up the alignment ?

Joined
15 September 2005
Messages
119
Location
Ellsworth, Wi.
I just had new tires put on the car, and want to have the alignment checked. I also will have new bilsteins put on some time down the road. Should I hold off on the alignment until the shocks have been installed, or go ahead and do it now??
 
95 CRUZER said:
I just had new tires put on the car, and want to have the alignment checked. I also will have new bilsteins put on some time down the road. Should I hold off on the alignment until the shocks have been installed, or go ahead and do it now??

You will have to get it aligned after you install new shocks.
If you are going to do the Bilsteins soon, I would hold off, otherwise you will be doing the alignment twice
 
definitely hold off until you have the new shocks on before doing the alignment. I just had my alignment done a week ago and im kicking myself because I plan to put on a set of new bilsteins and new springs very soon. Now I will have to have another alignment done after the install.
 
Daedalus said:
If you keep your perch at the same height and don't change the springs the alignment won't change.
Not true. I was told (by the Bilstein dealer) that the alignment is required, even when mounting it for the stock ride height setting.
 
If your last set of tires were wearing out evenly and that your car doesn't have any ill handling characteristic, then I'd agree with the earlier responses.

If you've been having alignment problems and are planning to put a lot of miles on the car, or you plan on attending some track events, before the Bilstein upgrade, then spending the extra $100 will ensure longer tire wear, safety and peace of mind.

An easy solution is to upgrade your shocks now and be done with it. :wink: You'll thank yourself if you have an older set of factory shocks now.
 
nsxtasy said:
Not true. I was told (by the Bilstein dealer) that the alignment is required, even when mounting it for the stock ride height setting.
I sure would like to know know his reasons. A damper by itself has no effect on static height or alignment.
 
I'm with Ken and bilstein on this one,not because the shocks per se change static ride height,but because alot of stuff gets loosened and unbolted in doing the swap.Therefore I would want to know that alignment was satisfactory rather than "looks good to me":wink:
 
docjohn said:
I'm with Ken and bilstein on this one,not because the shocks per se change static ride height,but because alot of stuff gets loosened and unbolted in doing the swap.Therefore I would want to know that alignment was satisfactory rather than "looks good to me":wink:

Agreed. Even if you're not specifically loosening any camber bolts, it is strongly suggested to redo alignment to ensure alignment has not drifted too far.
 
W said:
it is strongly suggested to redo alignment to ensure alignment has not drifted too far.

As noted, any "drift" in the alignment that is there now will wear those brand new shoes until the alignment is done. How long until new struts are put on "some time down the road"? Ensure the alignment is good now to maximize handling performance and tire life--IF the perch height isn't going to change.
I suppose when doing the struts a lot of stuff could get loosened by a wrench-happy knuckle dragger, but very little should by a proficient tech. Aside from ancillary things (lug nuts, plastic covers, brake brackets, window garnish, upper strut bar) there are 4 nuts/1 bolt on each front corner and 5 nuts/1 link on each rear corner that need to come off, NONE of which are touched when doing an alignment. The 2 procedures are independent of each other.
 
Daedalus said:
I sure would like to know know his reasons. A damper by itself has no effect on static height or alignment.

Thats not true, as dampers/shocks wear out the static ride height can change, so switching from old dampers/shocks would change the alignment and in so doing would require a realignment.
 
clr1024 said:
as dampers/shocks wear out the static ride height can change
A damper imparts a reactional force that is proportional to the speed of displacement. You can compress a brand new one with your bare hands and keep it compressed with little effort.
 
Measure the ride height before changing the shocks.
Use the method outlined in the Service Manual which you can down load on the home page of NSX Prime. http://www.nsxprime.com/FAQ/Reference/1991_svcman/1991_svcman.htm

Install your new shocks and recheck the ride height.
If it has changed, your alignment will be changed.
If the ride height has change, you will not have the same alignment numbers you had before the shock change, whatever they may have been.
 
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Daedalus said:
A damper imparts a reactional force that is proportional to the speed of displacement. You can compress a brand new one with your bare hands and keep it compressed with little effort.

as a mechanical engineer I realize this, but your static ride height can change as well.

PBasso is right he can check before and after height. In any case swithcing shocks he will have a slight alignment change as the install will not put everything back exactly where it was before. Its always a good idea to get a realignment after swapping shocks or springs.
 
clr1024 said:
the install will not put everything back exactly where it was before.
Everything should go back to where it was before. :) Come on, you can dig deeper than that. It's not much different than a bolted joint grip length tolerance analysis which, as an engineer, you've probably done more than a few of. Every part in the stack has a certain height. The total height is a sum of the parts. Of all the items in the stack, which one's height can vary, assuming correct assembly?
 
Daedalus said:
Everything should go back to where it was before. :) Come on, you can dig deeper than that. It's not much different than a bolted joint grip length tolerance analysis which, as an engineer, you've probably done more than a few of. Every part in the stack has a certain height. The total height is a sum of the parts. Of all the items in the stack, which one's height can vary, assuming correct assembly?

We could argue this for a while, since we are talking about fits the suspension pieces are bolted together using clearance fits on most parts, it means that nothing goes back to where it was originally, this would be different if using tight, interference fits or shrink fits, but we are not. This means that parts are in different places when they are reassembled than from dissassembly. How much may be small, but enough to change your alignment, to me it was worth it to get my alignment done after changing my shocks to bilsteins and know that it was correct and not wonder.
 
clr1024 said:
the suspension pieces are bolted together using clearance fits on most parts. This means that parts are in different places when they are reassembled than from dissassembly.
On that point I'll agree to disagree. Washers are loose-fit too, but I still know what they'll add to a stack-up.
 
95 CRUZER said:
I just had new tires put on the car, and want to have the alignment checked. I also will have new bilsteins put on some time down the road. Should I hold off on the alignment until the shocks have been installed, or go ahead and do it now??

How many miles are on your car?
How many miles did you get out of your last set of tires?
How did they look when you took them off, that is, what was the wear pattern like?
How long has it been, miles/time since you last aligned the car?


You should get your wheels aligned after you put on a new set of shocks on your NSX regardless of whether you do alignment now or not. The question is do you really need one now?

This is a a precision, performance vehicle, and minor changes on ride height do effect the NSX's alignment geometry. My advice is, when you change all the shocks on this car, especially with another brand of shock, is to do a wheel alignment, even if you aligned the car yesterday.
 
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Daedalus said:
On that point I'll agree to disagree. Washers are loose-fit too, but I still know what they'll add to a stack-up.

A washer is not a good example of a clearance fit in this discussion, as a washer affects an axial dimension/location,not a radial dimension/location and while not fixed is pretty repeatable in a reassembly. Also you have to account for things like bolt stretch and deformation during reassembly, my point is while all these things are small they will change you alignment, its a precision tool, and I would treat it as such. Unlike some of the guys I have seen rolling around with their cut springs, alignment way off or the car bouncing evey where because they have blown their shocks.
 
Diggning up an old thread... what if I remove my shocks to inspect and replace the bump stops/upper mount rubber and then put them back in? Do I need an alignment??
 
You don't need to. But your alignment won't be perfect. So yes, it is strongly recommended. Car will feel funny without.

Even if you do it carefully and put everything back exactly where it was....you will need an alignment. You can mark the alignment position and put everything back exactly, but it will still not be enough, it will need an alignment.
 
No. These other people are completely wrong. You aren't changing anything. Repair and replace. It's utter nonsense that if you take out the damper and put it back on without changing ride height, etc that you need an alignment. YES, in THEORY.... But the reality of the matter is that your alignment will change by a tenth of a degree. I have swapped springs, changed ride heights (small amounts to tweak ~ 1/4-1/2"), etc and had before and after alignments and the change was absolutely minimal. If you are changing ride heights by more than 1/4", then go ahead and get it done for piece of mind.

sent from my Evo4
 
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