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How many of you switch to an 87 octane tune during the winter months?

pixelzombie

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Chicago, IL, USA
#1
Right now I have the Stage 2 93 octane tune from Cobb. It's nice but I don't really need that extra power during the winter. I'm curious to hear what other members are doing.
 


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Fresno
#2
When I was on the stock turbo, I just switched back to stock tune and run whatever I feel like (87-93) when the gas run out. To me, 87 felt like a slug and I stopped using it after one tank.
 


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YO
#5
We've been running a 70/30 mix. 70% reg and 30% e85. We could go a bit more on the efuels, but this combo is working fine.
I know this is a bit old, but what are your impressions with this mix? Better mileage?

And to be clear, by “reg”, I assume 87–is that correct?

thanks for any and all input.
 


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#6
The only thing I will do differently in the winter (and still on the full factory tune) is never fill up with Sunoco 94 like I do when the ambient temps are above ~85*F.

I use the Shell V-Power 93 exclusively in the cooler/cold months.
 


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Houston, TX
#7
Honest question why change fuels in the winter? Assuming it's cuz traction in the snow limits you? I've always ran 93 winter and summer as I'm in Houston Texas so no snow.
The only thing I will do differently in the winter (and still on the full factory tune) is never fill up with Sunoco 94 like I do when the ambient temps are above ~85*F.

I use the Shell V-Power 93 exclusively in the cooler/cold months.
Why only use it when it's over 85? Can't you use the power as long as there is traction? Is there a cooling affect to higher octanes?
 


M-Sport fan

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#8
Honest question why change fuels in the winter? Assuming it's cuz traction in the snow limits you? I've always ran 93 winter and summer as I'm in Houston Texas so no snow.

Why only use it when it's over 85? Can't you use the power as long as there is traction? Is there a cooling affect to higher octanes?
In the summer, the 94 just gives a slightly better hedge against knock/detonation, possibly even LSPI(?), yes even within the Ford OAR, and knock sensor parameters.
I don't necessarily use it to gain the not even infinitesimal power increase it might yield.

Traction is limited in the winter not just from the cold ambient temps, (and the tiny bit more power anyway due to colder charge air temps via the intercooler), but also because I use narrower winter/snow tires and wheels, which are not made for ultimate accelerative, nor lateral traction.
 




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