mods that need an engineers certificate (ie, has to go over Dickson)
-Coilovers
-More than one intake mod (mods include pod filter, intercooler etc. they are usualy leanient on this one)
-Aftermarket turbos (an emmisions test is also required)
-Aftermarket wastegates and blowoff valves
-Engine swap (not to another RB25DET in this case but if you have a 25/30 or something)
-wheels that are drastically different to stock (ie track and rolling diameter has to be withing the ADR guidelines for modifications)
There may well be other but these are the only ones that applies to my car at the time
if you dont have any of the aboves then you should be right. I had coilovers and thus had to get an engineers certificate. cost $500-600