I'm making a new set of top wishbones following the picture bellow..
Can't find the original post but belive this gives good centering..
22mm from centre line..

Description
Thought i'd check with you?
Does this look all good to go?
cheers guys..

Hi
Our Indy did not self centre at all , so we got new top wishbones
with rose joints from MK , which gave us plenty of adjustment
Set caster about 7.5- 8 degrees & it now self centres some, not like
a regular tin top but definitely more acceptable


Stainless washers as crush tubes

I recently made some new top wishbones which give 10deg of caster angle, the previous ones were 5deg and gave very little self centering.

On the road these give almost tintop like centering but the downside is that the wheel becomes very lively, vigorously reporting back the bumps to a degree that gets a bit tiresome after a while. Probably a bit of bump steer involved in that too but it was the increase in caster that really made the difference here.

My conclusion was that somewhere around 8deg is about right. I think that's around a 30mm fallback with Cortina uprights but my maths isn't brilliant...

It also seems to depend on the weight applied to the front wheels to a certain degree, would imagine that a Pinto engined car will always need a bit less caster than a BEC or a K-series car like mine, so probably a bit of trial and error involved to get it just right....

My Pinto engined Indy had so little caster angle with the original MK upper front wishbones it made drivng hard work.

A pair of adjustable rose jointed wishbones from Talon improved things immediately. They are mounted almost centrally at present so theres plenty more adjustment on the caster angle available if needed.