kmckmc

Is this a simple task?

How to adjust the CASTOR on a 968. Just by loosening those 2 bolts on castor block? Somehow this 968's LEFT side (front wheel center to rear wheel center's distance is shorter by 1cm, compared to the RIGHT side) has slight alignment issue. The mechanic could not get the castor value within the standard spec.

Please help.

Jfrahm

The caster is easy, it's the big tab that sticks out from the caster block. Unfortunately that adjustment changes camber and toe a lot and so everything needs to be adjusted to compensate for the change. Odds are the tech is unfamiliar with the procedure, some use the caster adjustment to set the camber and overlook the camber eccentric on the strut mount. Then they wonder why the caster is wrong.

-Joel.

JimV8

What is the correct procedure? Is it start with castor, then camber and then toe?

kmckmc

I got a printout for today's alignment.

Front:
Castor: Before Alignment Left = 2.22degree; Right = 2.78degree
After Alignment Left = 2.10degree; Right = 2.65degree
(standard range: +2.5degree to +3.27degree)

Note: The change of value is entirely due to the adjustment of camber. This mechanic has no idea that castor can be adjusted earlier today, and he did not touch the castor block. And you can see that Left Castor value is out of range. The mechanic will attempt to adjust the castor block's screw in two days.

=======

Camber: Before Alignment Left = -2.28degree; Right = -2.12degree
After Alignment Left = -2.26degree; Right = -2.07degree
(standard range: -0.17degree to +0.17degree)

Note: This mechanic told me that old cars having more than -2.0 degree camber is not uncommon. Is this true for 968? Both sides' camber are way out of range.


What could I do now? This was the first time this mechanic did alignment for 968.

Jfrahm

Find a shop that can align a 944/968 or at least locate a camber eccentric on the upright (hint: It's the upper of the two bolts that hold the spindle to the strut.)

Old cars sagging to the point of lots of camber isn't uncommon but there is a decent range on the 944/968 and I doubt yours cannot be aligned.

kmckmc

That mechanic could do the camber adjustment. He said he could not improve the chamber to be more upright. Does this mean I should resort to a camber plate or getting new front shocks/springs?

kmckmc

What I am concerned is the castor value. The left side is just way out of range.

Cloud9...68

Joel,

If I'm not mistaken, maximum caster is achieved when the tab is pointing outward, parallel to the ground, right? The reason I ask is that I requested that the caster be set to maximum possible (my car is a mostly-track car), and I'm felling very little self-centering of the steering wheel coming out of a turn. However, I realize other factors (camber angle, tire width, ride height, etc.) could also be impacting the degree of self-centering I'm feeling. Thanks.

pontifex4

That's correct, though it's not uncommon to have to do this: caster, camber, toe, camber, toe.

I run more than that front and rear on a track car, but it should be possible to set your camber at 0 degrees (or even positive values) if you wanted to, assuming your ride height is at a somewhat reasonable setting.

I agree with what others have said previously: get him to set the caster so that both are equal, and make sure that he realizes that the camber is set with an eccentric bolt where the front strut bolts to the spindle that holds the wheel.

Jfrahm

I agree that he probably thought he was adjusting camber but was in fact manipulating the caster adjuster.

Re: the tab relative to the caster, I dimly recall that the tab on the caster adjustment aligns with the eccentric and thus minimum caster has the tab pointing towards the engine, normal is pointing down, and max is pointing out towards the wheels. If the car is aligned properly for street I expect the tab to point down, more or less. What do others recall?

155

FYI uou may have troubles with getting your castor set as a result of old warn bushings (if you haven't already checked this box). Elephant racing seems to have the best stuff out there. Also, IMHO I would take your alignment back closer to OEM. I ran -2.4 front camber and the front end felt light, darty and unstable at high speeds. We brought it back to -1.1 and what an amazing difference. Car feels like weapon.

pontifex4

That's roughly what I remember, as well. The tab can actually be turned with a 19mm wrench.

Cloud9...68

OK, thanks, I'll check which way my tab is pointing when I get home tonight. I had set it pointing outward when I took it to the shop for alignment, and specified that I wanted the caster as high as it can go. The car was down for my track car build project for so insanely long (over two years!) that I don't remember how the steering felt before, but I had expected to feel more steering wheel centering effect with the caster set to the maximim than I'm currently feeling, which has me wondering if the caster was set correctly.