Can i make relative delays in timequest (9.1)

I think you want something like:

set_max_skew -from [get_ports {sample_port}] 1.0

Then in your analysis be sure to run report_max_skew(Q10.0 has it run automatically).

Note that this will take into account on-die variation, which makes the numbers look bad. ODV is the fact that all numbers aren't the same at a corner. For example, at the slow corner, just because some path is analyzed as being worst case, all the other paths might not be quite that bad. This is a true phenomenon and is important for skew. So within a timing model like the slow corner, there are two sub-corners. When it analyzes skew, it will take the slowest path and use the slow-sub model of the Slow Corner, and the other three paths will use the fast sub-model of the slow corner. The clock skews will do the reverse. It tends to make the number look much worse than just doing:

report_path -from [get_ports {sample_port}] -panel_name "input delays"

and looking at the difference.