Setting valve lash on an 911 engine (.004) and the lock nut is out all the way to the bottom of the screwdriver slot (2-3 threads left).

Is this normal?

Mark - this was over on the Bird board today: http://forums.pelicanparts.com/911-engine-...t-adjuster.html
I don't know if that is the definitive answer or not....I don't have experience with the 6 but I thought I'd mention it anyway.

It has been awhile since i've done mine but that doesn't seem unusual.

I'd say its time for new longer length pushrods but I'm not sure many would get the joke.

I'm thinking these cams have been reground with a smaller base circle.

Have your rockers or maybe just that rocker been resurfaced ? Have your valve stems been re-surfaced ?
As suggested, swap it to another valve and put one of your other rockers on that valve. See what happens.