What type of gas?

[daddyowe]

Does it matter what grade of gas I use? The manual doesn't say anything about it. I've been putting in Premium, but I won't if I don't have to. Thanks,,,

[cryonchick]

I have used 89 octane since getting my boat ( 88' 351 PCM ) Runs great, no problems. Every now and tehn I will put a water remover/octane booster in a tank when I fill up, to ward off any troubles before it happens. I've heard of so many people with water and gas problems. If anything, you could probably go w/ 87 and add an octane booster ( provided no marine safety regulations were violated with using an octane booster in your gas, none that I know of ) and save a little bit more money. 10 to 20 cents more a gallon X 20/30 gallons to fill up vs. $1 to 3 for octane booster.

[suckmywake]

I have run Premium in my 87 Sunsport for the last 5 yrs and it really makes a big difference. On a long weekend, 20-30 gallons of use, if I run regular and there is some considerable idling in no wake zones it stalls out. That never happens w/ Premium. For the extra $, it's worth it. REMEMBER, it's a boat......a whole in the water you just throw $ into!! I don't mind paying to keep it running well!

[SupraNut]

The owners manual for my 1990 Sunsport calls for 89 octane (min.) so I use the Plus grade and never had any problems. The boat runs like a top!

[Salty87]

i go cheap, 87 and have no knocking. it depends on how old your boat is, newer rides have knock sensors and computers that correct for it by adjusting the timing.

go with the cheapest that works the best for your boat and your conditions.

i've also read recently that lead additives are a waste of money, for those of us with older engines that say to use leaded fuel. i'll post the link if i find it.

[Leroy]

Keep in mind the anti-knock system works by changing the timing and I'm told you lose quite a bit of power. I would go with 89 at least. Most boat engines are pretty high performance (and compression). Also gas loses octane over time. I've also used 87/91 and did not notice a difference, but the argument of so much money on the boat, so little to go with premium gas is strong.

[IndyMatt]

The Indmar owners manual calls for 89 octane minimum & that is what I choose to run through my engine. I think any grade of 87 or better will be fine, the danger comes in switching between grades as the timing is adjusted with the computer controlled knock sensor creates a greater chance of timing becomming incorrect.