Originally Posted by
91civicse
the manual says:
"gasoline requirements
your engine is designed to operate on unleaded gasoline with 91 research octane number or higher.
Research Octane Number (RON) is higher then the octane number shown on US and Canadian gas pumps.
91 RON is equal to 87 (R+M)/2 octane gas. The manual says to use 87 octane gas in somewhat misleading terms.