Can I use 89 Octane in my 2004 Mach 1?

Question

Its chipped and has SLP Exhaust and an KN intake.. I just bought it used and heard that I could use 89 octane instead of 91 is this true?

Answer 1

Everything that's been done to the car will make it run better and you should get better fuel economy if you drive it sanely. The octane rating of gasoline means that the higher it is the more controlled ignition it will have. You can try 89 but usually if it calls for 91 it must need it for proper operation in all aspects . You could floor it and it might ping instead of hauling as# Try it if you like but my brothers gt has to have 91 to run right.