Camber issue

[halg]

I have an issue with not being able to adjust camber far enough. With 1/4 " of shim on each side I only have 1/2 degree of positive camber. Of course I would like to get to negative but can't put more shim because the nut is to long for full engagement. I had a problem with my 71 where the chassis had moved in the factory assembly fixture so that 90% of the spot welds missed holding the left front fender on the car. I don't know if something like that could happen to change the alignment. All of the forces involved in driving the car(if something has failed) would tend to induce negative camber. I did not take care during assembly to insure that all slop in bolt holes would not make this issue worse. Will take apart to see. The A arms are not from this car. All new ball joints and bushings. Lower shafts were straight. The original cross member had a lot of shims(was not careful to document during didassembly) since everything was going to be new. I am contemplating increasing the bolt size from 8mm to 10mm and shifting the hole pattern for the ball joints. This would shift the upright in relation to the A arms. This would allow more negative adjustment.
Hal

[So Cal Mark]

are you using the stock crossmember?

[halg]

No I am not using the stock crossmamber. Dimensionally it is identical to the original
Hal

[So Cal Mark]

Is this in the new coupe or your Spider? Are your a-arms beefy enough to enlarge the ball joint mounting holes? The stock arms are pretty thin in that area

[kmead]

These cars are known for having the engine compartment shell spread open above the cross member where the upper shock/upper A arm mount as there is no way to link the structures together across the engine. This spreading would tend to induce more positive camber as the upper mount moves towards the outside of the car. The cornering loads on the suspension tend to reinforce and increase the spread and therefor more positive camber.

Your new crossmember (I recall seeing a couple of pics) could help reduce this by holding the upper mounts where they should be. If you replicated an old crossmember, you may have inadvertently included the distortion from the old one in your new stronger unit.

I wouldn't try to slot or change the holes where the ball joints mount, beyond spherical joints with threaded attachments you don't see adjustment in this area of the arm.

I would look at increasing the length of the bolts the lower A arm attaches to allow more shim material or preferably move the mounting plane the lower a arm mounts to outward by building it up or ?

As I recall the Haynes manual had the static points to measure to on the underside of the body, among them the factory locations for the front suspension. I would look at that and then measure those points on your car to see where you really are relative to the engineers intent.

[So Cal Mark]

as I recall I've seen more Spiders with the body collapsing in, so they have more negative camber than can be compensated for.

[halg]

This is on my new 69 Coupe. My mind says the upper end of the suspension should fail with increasing negative camber. This apperas to be something built into the car, since the original cross member had a large amount of shims installed. The car only had 24K miles.
Hal

[kmead]

Cornering loads would tend to have the upper mounts bow outward but the likely higher and more frequent loads from bumps/potholes would tend to cause it to push inward so you are likely right.

Given the above I would look into measuring where you are relative to the engineering intent before making other changes, especially slotting or changing the ball joint mounting locations.

[halg]

Ok I have set the car on a lift and accurately leveled it. Within .1deg side to side and .5deg end to end. Dropped a plum bob from the upper A arm attachment bolt on both sides and it measured 752mm, the book dimension is 750mm. That is in the direction I am having trouble with but probably within spec? The bolt holes that attach the ball joints to the A arms don't have any unusual extra clearance. My book does not have any specifications relating to the crossmember. My fabricated crossmember was originallly copied from a 72 and checks dimensionally with the crossmember from the 69. Does anyone have crossmembers loose that they would be willing to measure the mounting surface for the lower A arm pivot? See if there is any variation over the years.
Hal

[kmead]

The only crossmember I have out of my car is for a 2000cc car. I will go and have a look for it. Haven't seen it in a while, hopefully its not in my Coupe's trunk as its not accessible right now.

I have been searching high and low for the chassis chart for the 124. I have it for my 850 and my X 1/9 but cannot for the life of me find the one for the 124. I need to actually learn to file things. I will continue to search around for it.

2mm=.078 so that is quite a bit of difference, I suspect your first conclusion about how this particular coupe's body was built has always caused an alignment issue.

I presume you built your crossmember stout out of things you know about and as a result changing the bolts and mounting face is out of the question? At least longer bolts would allow you to stack a plate and then alignment shims to get to negative camber if so desired.

My recollection is that the primary change to the crossmember was lowering the engine mounts for the 2000cc motors and later for mounting the rack and pinion on the late Pinninfarina Spider Azuras.

[ventura ace]

Hal,
I have a cross member from a '76 that is out of the car, and my engine is out of my '70 spider at the moment (so it's crossmember is fairly accessible. What exactly do you need measured?

Alvon

[halg]

I need the dimension across the crossmember between the lower A arm mounting surfaces.
Hal

[ventura ace]

I'll call you tonight some time after 5 PM. (if I forget, please call me)

Alvon

[mdrburchette]

We just dealt with the same issue on our Lemons racecar. We couldn't get any negative camber on the left side so Craig pulled the upper A-arm and Ron cut it and rewelded so we could shim it appropriately. Of course, there's no telling why this car had the problem, but it's really a basket case and nothing we' ve done to it so far has been easy.

On my 71, I have the opposite problem. I'm sitting on 1 degree neg camber and have no shims in there to take out.

[ventura ace]

The crossmember from the '76 seems to have non-parallel surfaces. A little wider at the front, at almost 24 3/8", and narrower at the back, at about 24 1/8".

The crossmember on my '70, still on the car and not quite as easy to measure, seems to be much more parallel on the 2 surfaces, at about 24 1/8". The back may be just slightly narrower, but it is hard to say without taking it off for a good measure.

What does yours measure?

Alvon