We don’t have 93 or E85 here, or where it feasible to get. 91 is everywhere. Is it worth doings on 91? Is it bad for the motor? I have a f150 with a coyote 2017.
Just curious
I only run Clear Fuel
No ethanol
Iwpuld run this too if it was available. Stupid lesbo governor made e10 manditory and we have to buy alcohol abroad. Id yolo 1 tank with e85 and a tune for the lols.
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I have old school 5.7L tundra
It doesn’t want no corn in it’s fuel
It does not care about fuel efficiency
More power, cleaner engine
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Your engine wont last
Another 500k
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Have you tuned a car before? I would assume tuning for 91 would be no different than tuning for 93 or 89. The difference in the tune would be really small. E85 is a different beast. I could be wrong. Is it a stock coyote? Does it have any mods?
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Second gen tundras are hard to kill. People get 700k to 1 million miles on them. I should hsve bought one of those when I had that chance. Ill bet a second gen tundra will outlast a new tundra
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I bought it with a cat back and cai. It is stock. I spent a bunch of money changing all the fluids, some cooling system things etc. Might do a tune
tune for what you have.
I have two cars tuned for 93. Another tuned for 87.
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Yeah I’d tune for 91 and you’ll be set…otherwise if you got money to burn (literally lol) you can run octane boost.
My C6 is tuned for 93 and i carry a couple bottles in the back just in case I end up somewhere that doesn’t have it.
How much hp boost can you get in your car going from 91 to 93?
just throw a couple mothballs in the tank with your gas
I always carry whiskey in my truck so I justvthrow in a bottle of jack
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you just put hollywood undead in my brain so thank you!
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Not sure how scientific, but quick google showed this:
This set of pulls is interesting to me. I normally run 93 octane. I went for a drive where none was available and filled up twice on 91. I ran it down low and filled up with 93 and pretty much went to the dyno a couple of days later. There was no adjustments made between each pull. This was just the computer relearning 93 octane over 91. 2009 Z06 LS7, Billy Boat headers and exhaust, K&N air filter and a tune. In this configuration, it appears 93 octane is good for about 20 hp over 91.
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That sounds about right for a “large displacement” NA V8.
Turbo cars will see a little more but not that much. Depends on compression ratio, the volumetric efficiency and timing/spark knock threshold.
In short, there for sure is a power difference for a given engine tuned for 91 vs. 93.
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There is almost zero functional difference between 91 and 93 in your scenario, except that 91 may make slightly more power.
Unless you have the dynamic compression ratio to take advantage of the detonation resistance of 93, it’s a waste. If you don’t, 87 may make more power. With pump gas, lower octane has greater energy density, faster burn rate, better vaporization characteristics etc.
You only want to run the lowest amount of octane needed to prevent detonation/preignition for the timing curve and fueling strategy required. Anything more actually kills power (when talking regular gas, not oxygenated or specialty fuels).
When I worked in Top Fuel, people were always surprised to hear this tidbit- you start those engines on 85 or 87. If you tried using 93 it would never light off.
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You’ll be fine. The biggest tuner market is California and they don’t have 93. If you want to get spicy you could add water/meth injection.
That’s because it’s a c6 z06. A 99 f150 would gain ZERO and even lose power
Well he was talking about tuning so i made the assumption other mods/etc would be involved.
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