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Does 5.0 coyote performance improve with octane?

Q6543

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I’ve learned over the last decade, these coyotes LOVE higher temps… gotta shake the SBF 160* thermostat mentality

my cars fastest pass is usually after I drove it an hour to the track and everything is all heated up…. I’ll let it cool down for an hour etc… slower… without fail

they are meant for 200 plus.
 

robvas

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A lot of tuners have noticed how much S650 performance dies off on the stock tune as the car heats up
 

Bikeman315

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Even with a cold air intake, look at my IAT of 110 F compared to ambient 109 F. Also, here’s when it 115 F, but I didn’t catch the IAT. At a traffic jam or light, I get really high IAT, I’m assuming that’s when I need use point in octane I can get.

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I've always enjoyed my visits to Scottsdale, but damn I couldn't take those temps.
 

Sinthor 5.56

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Even with a cold air intake, look at my IAT of 110 F compared to ambient 109 F. Also, here’s when it 115 F, but I didn’t catch the IAT. At a traffic jam or light, I get really high IAT, I’m assuming that’s when I need use point in octane I can get.

IMG_1876.jpeg
IMG_1874.jpeg
Oh, I've seen my IAT as high as 123 in the past few weeks. Welcome to Phoenix!
 


DarkMatterGrey

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Oh, I've seen my IAT as high as 123 in the past few weeks. Welcome to Phoenix!
Yep, in traffic, at a stop light, on hot asphalt, at lower elevation, in the city (heat island). What drives me crazy is my wife's 5.7 Hemi Durango and my daughter's 3.6 Jeep Wrangler specify only 0w-20.
 

DarkHorseTT

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Hey, guys!

kindly give Your advise

I have dark horse handling pack, this season i want to make good numbers in atmo and next season to make Hellion TT + e85

so now in atmo, should I make tune for e85 and thermostat and that is all?

headers for TT I will need later special ones, cold intake I will not need later, id1300 and rfs fuel system I will need also only for TT
 

LouG

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...and you don't need a tune to run it?
I'm not sure where the cut off lies, but above a certain percentage ethanol the A/F leans out and ceases to make increase power.
I wonder if that's why E10 is normally the highest recommended?
 

Sinthor 5.56

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Time to install the Interchiller!
I have a main intercooler that's part of the supercharger package and then another. That won't help your intake temps though. Just the engine or transmission, I'm afraid. Even with that, my engine and oil temps are just high. Places like Phoenix....that's just how it will be. I've read that higher temps with high humidity can be at least as bad if not worse for engines. I don't know about that myself though...no way I'm driving to Florida this time of year to check!
 

Junkyard Dog

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Photos taken during an unseasonable cold snap here in August (Georgia). Each were taken after a drive of anywhere from 10 mins to 30 mins. Ambient air temperatures are displayed, ranging from 62° to 81°.

None of the pictures were taken after running a drag strip run or thirty minutes of track time. Just cruising to the gym or store or whatever.

Nothing anywhere around 228° for oil temperatures.
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