Octane Requirements

[Waverider]

Hello everyone. This is my first time posting. I recently purchased a brand new 2016 G23 with the 550 Supercharged engine. Prior to purchase, my dealer told me that I would need to run 91 octane fuel. I thought, okay, that will work except for when I go to Lake Powell and I will add octane boost. However, I just read the owner's manual and found out that I should be running 93 octane fuel. My boat runs great at my local lakes at 2,500 elevation. I have read that most octane boosts are really useless. What do you all do?

[swankster]

I bought a diesel tank off an old truck, cleaned it out and use it as a transfer tank. If I'm not where I can get the fuel I want, I bolt the tank in the bed of the truck and use it as a fuel shuttle. The lake I go to without fuel is a round trip of 40 miles.

[bradw]

I only run 98/93 in my boat at the end of the day a few cents a liter is cheaper than a rebuild. I've see two 409s blow up this summer from people putting the 91/87 octane fuel.

[lucky7t]

Blow up? You mean pop a head gasket correct ?

[Beg4wake]

The 409's don't require premium fuel though do they? If they did blow then it should be a warranty issue.

[Wayward]

^ not to mention, all of these engines have knock sensors for a reason. None of them will blow up from running 87 octane. They will simply back off timing advance, richen the fuel mixture, and have less power, on 87.

I did ask PCM about this before I ordered with the 550. They said that if I wanted full power potential that I should run 91+, but that it was ok to run 87 or 89. It just wouldn't be as powerful. More like 500hp on 87 octane. The fact that CARB testing is performed on 87, seems to back that claim, as it tested at around 510hp IIRC.