i have a 1985 ford range i ran reg . gass in it got 12 mpg. then i put med grade in it i got 15 mpg. ran reg . in lawn mower carbon build up locked the motor up cleaned the head . run nothing but med grade . no more probablem. car manufactury says you can run reg. gass in your va enguing butif your valves clatter go to a higher test gass . run nothing but med grade in my outboro. my motorhome sometimes pop a little super in it . i have a 1985 ford range i ran reg . gass in it got 12 mpg. then i put med grade in it i got 15 mpg. ran reg . in lawn mower carbon build up locked the motor up cleaned the head . run nothing but med grade . no more probablem. car manufactury says you can run reg. gass in your va enguing butif your valves clatter go to a higher test gass . run nothing but med grade in my outboro. my motorhome sometimes pop a little super in it .Did I miss something? Did Mercury buy wiseco? Putting 87 in an inline 1500 (made 73-77 and 78&79 if you include the identical 1400)and expecting it to last is like drinking a bottle of $5 tequila and expecting to feel good the next day.<br />If it was me (and since it's a 2.4 V6) then I'd compression test the motor and if it was 125 or lower I would run 87 in a pinch but run a 50/50 93 and 87 mix for a safety margin. I'd rather give a few bucks to my local rag head gas station than a few hundred or more to wiseco or pro marine. I rarely run all my gas out and the stuff tends to lose octane after two weeks even under ideal storage environments.
