GEN 2 Gas Octane Question

[500mag]

There's a station less than a mile from me that has 4 pumps ethanol free, 93 octane. Costs a bit more than regular premium. I use it for lawn equipment and for an old car I've got that has carburetors.

I always put 93 in my boat and waverunner because gasoline degrades about one octane number per month of storage.

 

[500mag]

91 all the time

Hard to find 91 in GA, usually 87, 89, or 93. Since I use Costco and Sam's, I just go for the 93.

 

[WRCRaptor]

The real question for me is how does the truck run overall in terms of smoothness and are there any long term reliability type disadvantages. My Gen1 ran a little smother on 91 or higher, it actually had a rough idle issue on 87. On that truck the HP gain was about 10hp as stated in the Raptor Supplement book and it is fairly impossible to feel 10hp by seat of the pants.

Not a Raptor but we had a 2003 H6 Outback and it said you could run 87 but recommend 91 or higher, the service guys all good friends of mine said only run the high octane as they had seen drivability issues and some injector problems. On the following gen Outbacks they are rated to run on 87.

I am seeing some conflicting info in the thread so what does Ford say in the owners manuals including the Raptor supplement? I don't have my Gen2 yet so I can't look, did I miss that post?

 

[xrocket21]

You guys all need to pull your 35s and put on 33s or something, youll gain like 3 mpg and be happier than a pig in shit

 

[EricM]

I don't think anybody is disputing the fact that you can see gains with 93 over 87. It is well known and proven. I think people are arguing the point that you can safely run 87 and have almost as much fun on your daily commute, should you choose to.

This guy gets a A+ in reading comprehension!

 

[EricM]

I always put 93 in my boat and waverunner because gasoline degrades about one octane number per month of storage.

I've had 12 month old 93 octane run through a high boost engine and there was no knock whatsoever. According to your math it should have been down to 81 octane at that point. Do you mean one "point" or 0.1 per month maybe? I don't disagree with you overall, over time you do lose the lightest parts of the fuel which tend to be the ones with the best anti-knock properties. With the sealed up fuel systems these days, it's not actually lost, but it all ends up in the charcoal canister and not in the actual fuel being dumped into the engine at high rates under WOT.

 

[500mag]

You guys all need to pull your 35s and put on 33s or something, youll gain like 3 mpg and be happier than a pig in shit

But....but....we runnin' 37s Bro...

 

[TurboTJ]

The real question for me is how does the truck run overall in terms of smoothness and are there any long term reliability type disadvantages. My Gen1 ran a little smother on 91 or higher, it actually had a rough idle issue on 87. On that truck the HP gain was about 10hp as stated in the Raptor Supplement book and it is fairly impossible to feel 10hp by seat of the pants.

Not a Raptor but we had a 2003 H6 Outback and it said you could run 87 but recommend 91 or higher, the service guys all good friends of mine said only run the high octane as they had seen drivability issues and some injector problems. On the following gen Outbacks they are rated to run on 87.

What? Typically you run higher octane to reduce chances of knock and preignition on engines with high compression ratios and forced induction. Why would the injectors care what the octane is?

I heard if you put 85 octane in, your gas tank falls off.

 

[EricM]

If I had an Outback I'd run whatever I could in it to destroy it so I wouldn't be stuck driving an Outback anymore. 85 octane sugar? Fill er up!

 

[xrocket21]

But....but....we runnin' 37s Bro...

BUT WHAT ABOUT THE MILEAGE? DODESNT ANYONE THINK OF THE MILEAGE?


and wont it rub if you take it offroad? wait....