I have Ruf wheels with spacers, all installed by the PO.
1. Are there enough engaged threads?
2. If not and I need longer ones, how does one determine the length needed based on specs when ordering? Is this a 2" lug bolt?

 

If the marks on lugs are accurate, it appears as though they are long enough. Too long and they protrude out of the back of the hub. They should thread the full depth of the threaded section of the hub at least. And maybe only 1 thread protruding out the back.

 

It looks too short to me. I'd call it a 1 1/4" bolt as that's the length of the shank. To me it looks like there is just over a quarter inch of thread engagement. The silver part of the shank would be the thickness of the wheel and spacer. Hard to tell without actually seeing the wheel and spacer.

Pull a wheel and spacer, install a bolt through both and measure how much thread is left to engage the hub.

 

Thanks guys. In looking at lug bolts online, I'm wondering how they are measured? From the shoulder? Just the threads? Total length? Clearly I need to convert to metric...

 

Maybe this will help

http://blog.moddedeuros.com/how-to-d...-or-volkswagen