Alignment question

underscore

Well-known member
From my understanding a macpherson setup has the same camber through the full range of motion, so can the camber be measured and adjusted while the car is in the air? Or does it need to be measured on the ground, lifted, adjusted, lowered, checked on the ground again, etc?
 

FC Zach

Active member
I am not positive but with the little training I've had on alignment, I can somewhat confidently say it needs to be on the ground for any measurements/adjustments.
 
underscore":a1shjs4u said:
From my understanding a macpherson setup has the same camber through the full range of motion, so can the camber be measured and adjusted while the car is in the air? Or does it need to be measured on the ground, lifted, adjusted, lowered, checked on the ground again, etc?
Put a straight edge level (bubble on vertical) across the wheel on the ground. Then lift the car up from the body and do the same thing. Is the angle the same? NO.

Put the car back on the wheels again w/o moving it - check the camber using a straight edge level again - is it the same as it was when you drove it and stopped and measured? NO.

That tells you something about how alignments can only be done.
 

underscore

Well-known member
I figured it couldn't be that easy, but everything I was finding about alignments was for other types of suspension so I couldn't tell for sure. The manual was no help either as it just says camber isn't adjustable.

Why does everyone say mac struts don't change camber while cornering if this isn't the case? Or is it just that it changes a lot less than other types of suspension?
 
underscore":527orzu2 said:
I figured it couldn't be that easy, but everything I was finding about alignments was for other types of suspension so I couldn't tell for sure. The manual was no help either as it just says camber isn't adjustable.

Why does everyone say mac struts don't change camber while cornering if this isn't the case? Or is it just that it changes a lot less than other types of suspension?
I'm not sure what the problem statement is here that you are trying to resolve. Perhaps the problem statement is talking with someone who understands suspensions and does alignments (not just capable of doing alignments to get the target specs).

Front end camber tips the top of the tire in towards the middle of the car when the suspension of that wheel is compressed (such as when turning right at speed, the left front suspension compresses, and the top of that wheel tips towards the center slightly). You need and want this because the car itself is tipping the opposite way (in a hard right turn, the body of the car tips down on the left-driver side). The opposite happens on the right side. All this happens to keep as much uniform pressure on the tire treads throughout hard turns. If it wasn't designed this way, hard turns would result in side loading the tires, resulting in smaller patch load on the tread and increased potential for skid, not to mention accelerated wear on outside edges of the tire tread.

Look at your lower control arm to the bottom of knuckle connection - that lower knuckle connection must follow an arc as the lower control arm pivots on its connection to the body. Now look at the strut angle and its connection to the upper knuckle. The strut doesn't pivot (relative to angular movement) at it's connection to the strut mounts on the body. So the top of the knuckle follows the strut angle as the suspension is compressed/relaxed. Given these two conditions, you can see how the wheel angle changes slightly as it moves. A model of this in a video would bring far more clarity than these words I'm saying will.

To make it a bit clearer, if the strut was near perfectly vertical instead of canted inwards towards the center of the car at the top, the wheel for a major part of its travel would have no camber change when the suspension compresses/relaxes. You don't see this kind of setup on any factory vehicles, for the reasons stated above.
 

underscore

Well-known member
At this point I'm just wondering why I was always told that a Macpherson setup has no camber change throughout the range of motion, as like you said the top of the strut is inboard from where the bottom of the strut mounts to the knuckle so the tire will have to pivot as it moves vertically. This was several years back though so at this point I can only assume those people were just wrong.
 
underscore":3sjxa11t said:
At this point I'm just wondering why I was always told that a Macpherson setup has no camber change throughout the range of motion, as like you said the top of the strut is inboard from where the bottom of the strut mounts to the knuckle so the tire will have to pivot as it moves vertically. This was several years back though so at this point I can only assume those people were just wrong.
You may have just misunderstood what they said. On most Macpherson strut suspensions, there is no camber adjustment that can be made in an alignment process. It can't be changed, as there are no adjustment mechanisms for such adjustment. Nor should there be any reason to change it - unless springs are sagging (which replacing the springs with original spec springs will correct this condition), or someone purposely alters spring rate or spring length (or both). Many who change ride height fail to understand the result on camber with Macpherson struts - and the camber angle is no longer proper for the vehicle.
 

FC Zach

Active member
93celicaconv":1ieb3h0t said:
On most Macpherson strut suspensions, there is no camber adjustment that can be made in an alignment process. It can't be changed, as there are no adjustment mechanisms for such adjustment. Nor should there be any reason to change it

But sometimes there are reasons (aside from incorrect/faulty springs) and in these cases there are cammed bolts just for that.
 

underscore

Well-known member
Side question then, if I replace my coilovers with a stock setup (which has no camber adjustment) without touching anything but the struts, will I still need an alignment?
 
FC Zach":1y7oxyuy said:
93celicaconv":1y7oxyuy said:
On most Macpherson strut suspensions, there is no camber adjustment that can be made in an alignment process. It can't be changed, as there are no adjustment mechanisms for such adjustment. Nor should there be any reason to change it

But sometimes there are reasons (aside from incorrect/faulty springs) and in these cases there are cammed bolts just for that.
The reference to cam bolts is almost always in regards to rear toe-in adjustments. This part of the thread has been talking exclusively front camber adjustment. At least on the ST185 (and all other 5th Gen Celicas), as is the case for most all (if not all) MacPherson strut front suspension systems, camber is not adjustable. Many rear-drive conventional front suspensions that utilized upper & lower ball joints do allow small camber adjustments - made via the addition/removal of shims associated with the ball joint connections.
 
underscore":r2rum6i4 said:
Side question then, if I replace my coilovers with a stock setup (which has no camber adjustment) without touching anything but the struts, will I still need an alignment?
Not if you know the entire history of the vehicle (assuming an ST185 here), and you know for a fact nothing has ever been touched on any front suspension component, and all control arms are in excellent shape (include control arm bushings) and have never been involved in any kind of unusual stress (such as hitting a curb with the side of a tire - almost all snow-belt vehicles driven in winter have had this happen though, and many times, the control arm gets bent slightly). So that would be your call. If you know everything is perfect and always has been, most likely nothing to be gained by getting an alignment.

That said, if I did what you want to do, I would at least get the alignment checked.

Front Camber:
- Inspection Standard: -10' +/- 45'
- Left / Right Error: 30' or less
- - Camber not adjustable - if measurement is not within spec, inspect and replace the suspension parts as necessary

Front Caster:
- Inspection Standard: 1 deg 00' +/- 45'
- Left / Right Error: 30' or less
- - Caster not adjustable - if measurement is not within spec, inspect and replace the suspension parts as necessary

Steering Axis Inclination:
- Inspection Standard: 14 deg 10' +/- 45'
- Left / Right Error: 30' or less
- - Steering Axis Inclination not adjustable - if measurement is not within spec, inspect and replace the suspension parts as necessary

Toe-In:
- Adjustment Standard: 0 +/- 1mm
- Tie-Rod End Length Left/Right Error: 1.0mm or less
- - Adjust tie-rod positions as necessary
 

underscore

Well-known member
93celicaconv":qdfo7ew3 said:
Not if you know the entire history of the vehicle (assuming an ST185 here), and you know for a fact nothing has ever been touched on any front suspension component, and all control arms are in excellent shape (include control arm bushings) and have never been involved in any kind of unusual stress (such as hitting a curb with the side of a tire - almost all snow-belt vehicles driven in winter have had this happen though, and many times, the control arm gets bent slightly). So that would be your call. If you know everything is perfect and always has been, most likely nothing to be gained by getting an alignment.

Yes this is for my 185, it came from Japan so no clue how it was driven there. Once it got here it stayed in a part of the country that only gets snow maybe 2 days a year. Since then I've replaced all the suspension bushings and had it aligned a couple of times, most recently about 5000km ago. I might just check the alignment myself after and if everything looks close and it drives well I'll leave it, if something is out of wack I'll bring it to a shop.
 

FC Zach

Active member
93celicaconv":zeekkiv3 said:
The reference to cam bolts is almost always in regards to rear toe-in adjustments. This part of the thread has been talking exclusively front camber adjustment. At least on the ST185 (and all other 5th Gen Celicas), as is the case for most all (if not all) MacPherson strut front suspension systems, camber is not adjustable.

My mention of cammed bolts was in regards to adjusting camber, whether it be front or rear. . Was just throwing that option it there if underscore needed to make adjustments since it's not uncommon.
 
FC Zach":q38ytmao said:
My mention of cammed bolts was in regards to adjusting camber, whether it be front or rear. . Was just throwing that option it there if underscore needed to make adjustments since it's not uncommon.
But the ST185 has no cammed bolts to adjust camber. Or is underscore talking about some other model vehicle?
 

FC Zach

Active member
45643822744_809a0bf207_z.jpg
 

FC Zach

Active member
Typically these bolts are used to replace just one bolt. . I've never seen two per strut. . that first image is just for an example.

45453983785_25f252bdec_z.jpg
 
Thanks for sharing. I did not know they made these kind of substitute bolts for the strut connection to the knuckle. Learned something new today. Thanks, FC Zach.
 
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