??
1) The boxster came with lug BOLTS, not nuts. So, unless you converted your car to studs and nuts I am confused.
2) What do you mean they only "stick out about .80 of an inch"?
3) An SCCA type guideline I recall for wheel bolt/lug engagement is "13 turns" of the said nut/bolt. I have also head it said that you want engagement at least equal to the diameter of the bolt head/nut in question
So.. what was your question exactly? Don't be afraid to write out a nice description of your situation too