I found this updated book for our 2002 sentra se-r and spec v are specified now.
http://www.nissanextendedwarranty.co...san-Sentra.pdf
It says:
FUEL RECOMMENDATION
For 1.8L/2.5L engines
Use unleaded regular gasoline with an octane
rating of at least 87 AKI (Anti-Knock
Index) number (Research octane number
91).
For SE-R SPEC V
Use unleaded regular gasoline with an octane
rating of at least 87 AKI (Anti-Knock
Index) number (Research octane number
91).
For improved vehicle performance, NISSAN
recommends the use of unleaded premium
gasoline with an octane rating of at least 91
AKI number (Research octane number 96).