I have a Fountain that requires 92 octane. I live on Puget Sound and would like to meet up with my buddies in the San Juans (round trip beyond the range of one tank). The marinas are only going to have 87 octane available. Has anyone had experience with octane booster products?
I could fill up with 87 when I am 1/4 or 1/2 tank down and add a booster. I can also take it real easy on the throttle but I would not want to harm the engines. Your personal experience would be appreciated.

https://boostane.com/?gclid=Cj0KCQjw...gaAgveEALw_wcB

Check these guys out. I have not used them in a marine application but I have on high compression Harley motors. Others here may be of better help to you...

Most of them really only raise the octane a few TENTHS of a point...I have no experience with the posted product though. My '93 twin-turbo RX-7 really prefers 93 octane but I just can't get it in my area so...the ECU is mapped for 91 octane currently because of this and the ineffectiveness of octane boosters. I really don't know what you can do other than take it kind of easy, as you note. If the engines are FI, they should protect themselves with slightly reduced performance, if older/carbed...be careful.