87 octane regular
That was a real low horsepower engine in that model so I think you can get away with regular in it.
Between 165 and 225 depending on exactly which model. http://www.thirdgen.org/1987-pontiac-firebird
19 City 31 Highway
There are 4 different rating systems for Octane. What country you buy you gas in determines the rating system in force in you area. There is a very good WIKI article about this and I recommend you read it to understand what Octane rating is in use where you live.
The octane rating of methanol depends on the octane rating scale measurement type used, n-Heptane is the zero point of the octane rating scale then the octane rating of methanol is 115
The lowest. You will be wasting money if you get a higher grade.
Unleaded is choice. Manufacuters recommend a minimum octane rating of 87. In high altitude, 85 octane is acceptable.
V6's ranged anywhere from 200-212hp
It has no octane rating.
yes i use it when i do alot of city driving but on the hwy i would recommend 93 octane
16 city, 24 highway, depends largely on how u drive it. check out fuel economy.gov