JohnC

Hey guys. This is my first post although I've been a lurker for awhile. Mostly because you guys drive boats that are faster at quarter throttle than my Donzi Sweet 16 at WOT But I have a question that I don't trust to just any boating board.

My Donzi has a stock Ford 302 HO engine. (C'mon, don't laugh) Probably around 205 HP and I guess no more than 8.8-9.0 CR. I've been using 89 octane gas (per OMC) with E10. I just found a local gas station that sells non-ethanol gas but its 87 octane. I tried it today and heard no pinging or other issues.

Here is my question: should I stay with 89 octane with ethanol or use 87 octane real gas?

Thx for your input, John C

Griff

So the engine has a recommendation of 89 octane minimum????

It is doubtful that you will ever hear pinging in a boat until it goes boom. I would avoid E10 fuel if you can, but if you need 89, it does not sound like there is much of a choice.

Is there any 91, 92 or 93 available without ethanol??? You could mix it with the 87.

JohnC

I re-checked the manual and it says 89 octane and its OK to burn E10. OTOH, when I gassed up I also found he sells race gas. I took a quick glance at the pump and saw two of the grades are 100 and 110 octane. Unfortunately I didn't see if its E10 or not. I'll be driving by the station later this week and will post that info.

John C

Griff

The race fuel will not have any ethanol, but will get pricey.

Kidnova

I asked my engine guy a similar question. My engine is a bit different than yours (557ci with 9.3 cr). I've always run 91 or 93 octane however I found eth free 89 at a local marina. I asked if it would be ok to run the 89 eth free. I was told that basically, octane is octane regardless of the ethenol content. So, guess I'll stick with the 91 or 93, with the ethenol. Sux but it is what it is.

When I gas up I try not to let it sit in the tank too long... buy it and use it.

JohnC

You're not kidding. $9/gallon. And from a site search it looks like octane booster is mostly bunk. I appreciate the benefit of your experience guys.

John C