Originally Posted by CantRepeat
Everything I've read says 87 for 351w/302 and that's all I ever ran in my 92. I guess it's just a matter of how long it sits before use and whether or not that it was stabilized.
Here is the page from the 91--93 Owner's Manual. I believe the reason they recommend 89 (per Indmar) is that 87 is okay, but 86 is not. Boat gas sits around. For what it's worth, the 351 (GT40) in my 98 Ski Nautique calls for 89 as well. I'd feel more comfortable putting 87 in that boat since it has a knock sensor. But I don't.
As the saying goes, your boat, do as you like. But the manual for that year undoubtedly says 89 octane.
For a full tank, that's about $3--5 more around here. I don't tend to miss it in the grand scheme of things. Then again, my VW takes 93. So getting to put 89 in something is a picnic.
Previous: 1993 Prostar 205
Red 1998 Closed Bow Ski Boat, PCM GT40, 310 hp, Standard Gear Reduction, Acme 4 blade, Perfect Pass SG/Zbox.
Tyler Ski Club
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