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2017 ST2, K&N filter, Exhaust, Turbosmart Kompact Dualport BOV, true vacuum port, symposer delete
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Discussion Starter · #1 · (Edited)
So ive searched the fourm for an answer, but havent found an exact result on the hp difference. Im thinking about getting the stratified flash tune, but i dont know if it is worth the extra $75 for both the fuel types. I just want to know the difference between the HP numbers, i could care less about the extra money. I just wanna know because 93 is 50cents more expensive per gallon.
 

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You live somewhere where you readily have access to both 91 and 93? Yes, all things else equal, maybe ~10hp difference between the two. I would tune for the fuel you are most likely to see and use. FYI, you can use 93 octane with a 91 tune (would be safer) but you shouldnt use 93 on a 91 tune. Its not as dramatic of a difference as using E30, if paying for a second tune and you have access to e85, i would do that.

I dont think i have seen anyone provide dynos on this car with a 91 vs 93 tune. I am not sure where, under the curve, the gains are or if only at the peak
 

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2018 Focus ST Magnetic Metallic
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I got both 91 and 93 maps from Stratified. I'm happy I did. It makes it great for travelling between states who have different octanes.

Slot 1: 91
Slot 2 : 93
Slot 3: 93 with rev limit (for when my friends/family occasionally drive my car)
Slot 4: Low Boost/Winter
Slot 5: Valet Mode (never letting anyone valet my car so kinda useless. But a lot of people use it for when they drop it at a dealership.
 

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2017 ST2, K&N filter, Exhaust, Turbosmart Kompact Dualport BOV, true vacuum port, symposer delete
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40 Posts
Discussion Starter · #4 · (Edited)
You live somewhere where you readily have access to both 91 and 93? Yes, all things else equal, maybe ~10hp difference between the two. I would tune for the fuel you are most likely to see and use. FYI, you can use 93 octane with a 91 tune (would be safer) but you shouldnt use 93 on a 91 tune. Its not as dramatic of a difference as using E30, if paying for a second tune and you have access to e85, i would do that.

I dont think i have seen anyone provide dynos on this car with a 91 vs 93 tune. I am not sure where, under the curve, the gains are or if only at the peak
"you can use 93 octane with a 91 tune (would be safer) but you shouldnt use 93 on a 91 tune"
is this a typo, or do you just mean i can use 93oct on 91 tune but i shouldnt? im interpreting this as "is you can use 93 on 91, but you shouldnt use 91oct on 93 oct tune." also, i do have e85 access, but it is a good 20-25 minutes away. i do go out there sometimes for other reasons, but not alot. What is the power like between 93/91 and e85?
 

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"you can use 93 octane with a 91 tune (would be safer) but you shouldnt use 93 on a 91 tune"
is this a typo, or do you just mean i can use 93oct on 91 tune but i shouldnt? im interpreting this as "is you can use 93 on 91, but you shouldnt use 91oct on 93 oct tune."
93 octane with the 91 tune is safe (using a higher octane fuel on a lower octane tune)

Do not use a lower octane fuel on a tune for a higher one, you will increase chance of knock.
 
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