According to Fast German Auto, they first tried to use the same 8mm as the
stock allen bolts, but these did not work because the threads were too thin.
(Because of having to drill out the bolt to fit the zinc rod - I'm assuming.

Todd
'88 Westy

Per Lindgren wrote:

> Todd Last wrote:
>
> > FYI - Just got confirmed by Fast German auto that the Z-sticks are 1/8"
> > pipe thread which require retaping the threads in the head in order for
> > them to fit. They are not a 'drop-in' replacement.
>
> Apparently not designed with a German car in mind. Are there any of these
> with metric threads around? Maybe re-thread the sticks instead of the head,
> and use an intermediate thread piece to make it fit? I sure wouldn't
> re-thread the heads to make it fit.
>
> PerL
> 87 Syncro 112i