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LopinLH
08-11-2013, 12:07 PM
Hey guys -

I am probably just being paranoid, but I have a fuel octane question. I have the 6.0L 409 HP Indmar engine and the owners manual says to run fuel with a minimum of octane rating of 91. I have about 40 hours on the boat and I have done this to this point. We are going on a trip and will need to fuel on the water, and based on a few phone calls to marinas on the water most carry 87 clear (no ethanol). Is there any risk in running a tank or 2 of this through my boat?

Thanks,

Luke

beat taco
08-11-2013, 12:12 PM
Bring some bottles of octane booster with you.

xBabyJesus
08-11-2013, 03:41 PM
It takes quite a bit of octane booster to get that kind of increase. Read here:
http://volvospeed.com/Review/misc_performance_volvo_reviews.html

-J

parrothd
08-11-2013, 04:49 PM
It'll just run with less power and use more fuel... The computer will retard the timing with the lower octang...

Sent from my Nexus 4 using Tapatalk 2

NateHaskovec
08-11-2013, 07:32 PM
Listen for knocking. If you don't hear it (sounds like marbles in a coffee can) you are not hurting the engine at all.

With knock sensors, you will almost never get detonation out of 87 octane.

ian ashton
08-11-2013, 10:10 PM
It seems odd that you can't find higher octane on the water - our lake has 87 with ethanol, and 91 without. I opt for the 91 :)

beat taco
08-12-2013, 01:05 AM
Only 87 at Shasta. I run it. The MC gets booster.

LopinLH
08-12-2013, 06:11 AM
Only 87 at Shasta. I run it. The MC gets booster.

Hey Jake what octane does your engine call for? What booster do you use? I am hoping to find some higher octane on the water but I picked up a couple bottles of Lucas Oil Booster in case....

-Luke

sandm
08-12-2013, 06:56 AM
as mentioned above, there have been several car mag tests on octane boosters and most won't raise it enough to make it worth your money. remember that if it says it'll raise it by 5 points, it's not 87 up to 92, it's 87 to 87.5 and that's a maybe.
just don't run the engine wot and take it a little easier on it. the computer and sensors will do the rest.

beat taco
08-12-2013, 11:49 AM
Hey Jake what octane does your engine call for? What booster do you use? I am hoping to find some higher octane on the water but I picked up a couple bottles of Lucas Oil Booster in case....

-Luke

The Supra gets 87 and nothing else.

The 6.0 ilmor in the MC gets Torco Accelerator which I believe is good for 20 points so would raise it to 89.

What these guys are saying is true about the knock sensor, it will protect the engine and you can run 87. But for better performance run 93. That's exactly what the ilmor manual says.