Flashpro 91 vs 94 octane

ayau

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BS. The factory tune is tuned for 91 octane and adding additional octane won't do anything.

As far as I'm aware there's no realtime octane sensor manufacturers can just shove in the fuel line like an ethanol sensor.
I believe on the factory tune, there's a little ignition retard on 91 octane. If you run 93 or higher, then you'll have 'maximum' power from the factory tune.

Go to 15:20 where he talks about the tune being universal and the only difference being the octane where the car is being sold. UK has 98 RON, which is about 93.5 AKI (US octane).

Furthermore, Hondata said the factory map is tuned for 0% ethanol. In the US, nearly every station has 10% ethanol. The 91/93 Hondata maps adjusts the tune to account for the 10% ethanol by adding additional fuel. If this isn't adjusted, the factory fuel trims will probably always add a few percent short/long term fuel to reach stoich. This further supports that the ECU was tuned with UK gas, which ethanol isn't as prevalent.

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kefi

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I believe on the factory tune, there's a little ignition retard on 91 octane. If you run 93 or higher, then you'll have 'maximum' power from the factory tune.

Go to 15:20 where he talks about the tune being universal and the only difference being the octane where the car is being sold. UK has 98 RON, which is about 93.5 AKI (US octane).

Furthermore, Hondata said the factory map is tuned for 0% ethanol. In the US, nearly every station has 10% ethanol. The 91/93 Hondata maps adjusts the tune to account for the 10% ethanol by adding additional fuel. If this isn't adjusted, the factory fuel trims will probably always add a few percent short/long term fuel to reach stoich. This further supports that the ECU was tuned with UK gas, which ethanol isn't as prevalent.

You might be right. It would make more sense for it to be tuned for 93, especially with what you said.
 

armenls1

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I remember when HondaJason visited the Type R plant in Swindon and was talking to the British dude about the reason UK version is rated higher HP than North America. He asked him if the NA version was to put higher octane in it would run at the higher number.... can't find that video right now but i'm sure some of you have seen it. It all has to do with the car having a low octane and high octane table. I'm still stock for the moment, (waiting to have fuel pump recall services before doing anything), and have been putting 94 in my CTR as soon as the first tank was done from the dealer. I've always put 94 in any performance car.... I was under the impression that the fuel trucks come with a 87 tank and a 94 and then mix is done on the spot, lol, probably wrong about that but damned if I want to find out if the mixture is done right.
 

ayau

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I remember when HondaJason visited the Type R plant in Swindon and was talking to the British dude about the reason UK version is rated higher HP than North America. He asked him if the NA version was to put higher octane in it would run at the higher number.... can't find that video right now but i'm sure some of you have seen it. It all has to do with the car having a low octane and high octane table. I'm still stock for the moment, (waiting to have fuel pump recall services before doing anything), and have been putting 94 in my CTR as soon as the first tank was done from the dealer. I've always put 94 in any performance car.... I was under the impression that the fuel trucks come with a 87 tank and a 94 and then mix is done on the spot, lol, probably wrong about that but damned if I want to find out if the mixture is done right.
The video was posted like 2 posts above yours lol.
 


 


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