Manny high performance automobiles require premium fuel. Most United States domestic family automobiles do not require premium fuel and will run fine on 87 octane fuel.
According to the link below these four cars require premium unleaded fuel.
Upper-end cars use Premium fuel
Unleaded, diesle, premium and super
only use premium fuel in European cars,
Premium is recommended for the ETC models
Most cars in the USA require gasoline as fuel.
premium fuel should say on the inside of the fuel door
Assuming you're referring to a petrol car, it depends on the car but most cars can run on unleaded. Some do require require 4 stroke or premium fuel to run at optimum efficiency
Most cars require 87 octane. You can choose to gas up with a higher octane but it will not be necesary. Simply check your owners manual it will tell you whats required
I have used regular for years with no problem.
It is not just the 07 Civic SI, but the Honda Civic SI made after 06 requires premium fuel because it has a strong engine. It runs more smooth on premium fuel than regular fuel. Regular fuel will eventually damage the engine.
Premium. Octane rating of 91 or higher.