Hi BIX !
Im no Nissan Tech but think I might be able to point you the right direction here as to wether or not to junk her out .
Generally speaking you need to ask the right question .
A lott of car's in the 80's and 90's Hondas / Toyotas etc had head's that were considerd interference type head's .
Meaning if they jumped time the valves would hang open and the piston would come up and smack up .
This generally bent thing's up pretty badd .
Later they came out with what is considerd to be a no interference head these didnt allow the valve's to hang low enough that the piston would hit them .
So the question you need the answer to is wether or not your ride has a interference type head's or, a no interference type head .
Unfortunately I can not answer this question as Im lost when it come's to high end Nissan's and seem unable to find manual's on the Q45 Infinity .
But I did stay at a Holiday Inn once ?