164 Camber

[VLADDS@domain.elided]

"And does it bother anyone that
changing the spacers on the smaller bushing-to-frame leaves the rear point
the same, in effect cocking the "A" frame -- does that change caster or
toe?  Only trivially?"
Richard:
 Remember that the length of the strut is variable. If you hold the strut 
length fixed, say at maximum travel outward, and then reduce the distance 
between the ball joint and the chassis, you would put a torsion stress on the 
A-arm. However, the length of the strut changes, and compensates for the 
modification of the abovementioned distance. The position of the A-arm with 
car "sitting" on its wheels is influenced by an equilibrium between the 
amount of total weight distributed on that wheel and the force of the spring. 
That means that the A-arm's position will remain unchanged (not cocked, or 
angled away from its "neutral" position). The 5-8 mm worth of travel of the 
ball joint towards the chassis will be compensated by travel of the shock 
rod.
As far as camber, caster and toe.
Toe is adjustable and will not be modified with this beyond its adjustable 
range (I can post my alignment sheet if this helps).
Camber, as I explained becomes (in a small range) adjustable
The frozen caster is preserved, and here is the major advantage of this 
modification versus ovalizing the holes at the strut top. Bill is right 
saying that a small amount of mod up there has a relatively big result in 
angle change. But that has its drawback too. A very small amount of 
ovalization with the axis of the oval not perpendicular on the longitudinal 
axis of the car (and how do you insure that you ARE perpendicular?), will 
change the "frozen" caster, because now you have angled the strut in a 
vertical plane, as from looking at it sitting in front of the wheel.
With the mod I suggest, I have checked the thickness of the washers with a 
caliper and they seem to hold a quite acceptable tolerance, so it's safe to 
assume that they're equally thick and with an identical number of them on 
both mounting points, you have kept the pivoting axle of the A-arm parallel 
to the chassis.
Now the design of the suspension allows the A-arm to travel closer to the 
chassis. That's why there are bushings on it and a bushing at top of the 
strut that allows it to angle.

My objection to the ovalization of the holes up top is also because although 
it's a simple thing to do, it can probably never be brought back to original. 
If you work on it with welding equipment, you could change the mechanical 
characteristics of the steel in that plate and even cause thermal stress. The 
end result will be that there will be a number of 164 that in time will 
become available to others that want to keep them original, yet there will be 
little you can do to bring them back. Should I mention that if you look 
closely at what happens with the mounting points at the top, if there were a 
stress on the bolts to move them sideways (inside that oval), the only thing 
preventing them from doing that would be the tightness of those nuts?
But Again, Bill is right, if you lower a 164, you do what you have to do, and 
I agree that what I suggested might not be enough in that case.

To look at what others do with their cars, you're right about VW. I had a 
Scirocco and saw that eccentric upper bolt. Maybe the stress that was taken 
into consideration at the strut bottom-hub assembly, is higher in the case of 
the Alfa than the VW and that adjustable bolt was considered too weak.

If you look at what BMW fans have available, they have an adjustable strut 
plate, on aftermarket. I think it installs in the strut assembly and provides 
those mounting bolts to travel in an "organized" way   : )

Sorry for the length of this, take care everyone
Vlad
'91 164L
'85 Maserati Biturbo S
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