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Best Gas For FL5?

Integra23

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Where are you finding this 92,94 octane? I mostly see 87,91,93
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ayau

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So 92 octane fuel using ethanol performs better than 92 octane fuel without ethanol ? Octane rating denotes the resistance to knock, so a 92 with ethanol is the same as 92 without ethanol. Same applies to any octane but I just used 92 in this example.
92 with ethanol isn't the same as 92 without ethanol. More ethanol means more knock resistance given the same octane number.
 

tuhroo

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i don't get it...where in florida do you NOT have 93? it's at every station i've ever been to lol
 

ssheff55

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93 Shell 95% of the time. 93 BP if I can’t find Shell.
 


mbaapk

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Sams Club 92 or BP 93 ftw.

Anyone know what that recreational fuel at Kwik Trip is?
 

POPNTEC

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Should I pick up 93 if it is available near me? Keep in mind my elevation is around 6500ft so I think 91 is basically 93 at that point.
Wait what! Octane increases with elevation???

I’m at 1200 ft and I get 94 octane…
 
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Rad Ray

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i don't get it...where in florida do you NOT have 93? it's at every station i've ever been to lol
Tampa Bay has (according to finder apps) a few, but none within 10 miles of where I live.
 

ayau

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Sams Club 92 or BP 93 ftw.

Anyone know what that recreational fuel at Kwik Trip is?
jet skis, lawn mowers, etc. it’s for motors that don’t use up the gas. Ethanol absorbs moisture. Bad for gas. Not an issue for cars since it gets used before it goes bad.
 


ayau

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The oxygen is richer at higher elevations
I think you got it backwards. Higher elevation means less oxygen.

Still not sure how you concluded correlates with octane.
 
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CyberCTR

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I think you got it backwards. Higher elevation means less oxygen.

Still not sure how you concluded correlates with octane.
Yeah you’re right. There is less oxygen, but for some reason the elevation affects octane and it may correlate with less oxygen to fuel ratio but I’m not certain.
 

TheCanadian

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FK8 had no benefits from mods or higher octane above 91 unless the ECU was tuned. I'd assume the FL5 is the same. So stick to 91 octane. Anything lower = bad idea. Anything higher = wasted $$
 

ayau

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FK8 had no benefits from mods or higher octane above 91 unless the ECU was tuned. I'd assume the FL5 is the same. So stick to 91 octane. Anything lower = bad idea. Anything higher = wasted $$
Not entirely true. I'm unable to find a 91 vs 93 factory tune FK8 dyno, but pretty certain there's a small amount of knock on 91. Knock means timing retard, which means less power.

It's also why European spec FK8 is rated higher HP than US FK8. Both ECUs run the same factory map but US is rated on 91. Factory tune is also assuming there's 0% ethanol and the US has 10% ethanol. More reason to believe the factory tune is universal for all markets.

Technically there's still benefits to running 93 even if you don't believe the ECU knocks on 91. You're increasing the knock resistance. Every engine will produce some sort of knock given the right conditions (temp, load, etc). The cost difference between 91 vs 93 is marginal. The bigger issue is having access to 93.
 

TheCanadian

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Not entirely true. I'm unable to find a 91 vs 93 factory tune FK8 dyno, but pretty certain there's a small amount of knock on 91. Knock means timing retard, which means less power.

It's also why European spec FK8 is rated higher HP than US FK8. Both ECUs run the same factory map but US is rated on 91. Factory tune is also assuming there's 0% ethanol and the US has 10% ethanol. More reason to believe the factory tune is universal for all markets.

Technically there's still benefits to running 93 even if you don't believe the ECU knocks on 91. You're increasing the knock resistance. Every engine will produce some sort of knock given the right conditions (temp, load, etc). The cost difference between 91 vs 93 is marginal. The bigger issue is having access to 93.
I can promise you with every fibre of my body that there is NOT knock on a factory stock FK8 when using the fuel octane it is specifically designed for (91). How knock works on the FK8 is documented over at the Civicx forums.

Essentially the Bosch ECU will retard timing from knock and forget everything when you take your foot of the gas and repeat. The factory tune is ready for ethanol. Honda would not sell a car that cannot be fuelled in the continent in 99% of stations. I don't have the exact laws but I'm 100% positive is federally mandated to accept ethanol.
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