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funny you mention v10 triton. My class c has it in the e450 frame. Always 8.5mpg at 87, doing all this trial and error, i loaded up with 91, no small feet at 50 gallons. No mpg gain noted yet, but seems more power during long steady climbs.
No, a Dodge V10, it’s a torque monster since the upgrades, HP just modest gains but did get ~1K more useable RPM.
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YBABRAT

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Are you able to provide any proof that modern engines (and fuel systems) are harmed by regularly using ethanol-blended gas? Or is this mostly anecdotal, an old wives tale?
Most don't see knock as an issue. When computer will retard timing accordingly. Ethanol hides knock and having a rich fuel mixture as well.

Under load and heat... mountain trails and also towing will cause ping with 87. It's a no brainer!

Giving gas to add to the issue of lacking power, can be detrimental.

I had a discussion about turbo 4 cyl. When someone brought up the Alpha Romeo engine. Supposedly the same inside the Jeep.

They had no clue as to the issues with the engine until I posted my reply. The issue is fuel in oil contamination. Due to the fact. The turbo 4 cyl has direct injection the type of system has a flat with fuel leaking through the cylinders. It cut down oil life in half. The band aid was to replace oil pan with a 6 quart pan. So standard oil replacement routine is not affected.

Not that all engines have this issue, but bad burn and over compensation with throttle can allow gas to leak past cylinders to contaminate oil. More likely to happen with higher milage engines.

It's not the Ethanol directly doing damage, it's how inefficient the burn cycle effects oil. Cleaner burn better oil life, less wear. As for ping and heat they can cause damage and most are unaware what's happening as computer and low grade gas try and hide the issue.

Like I said... flat landers won't be effected as much.

Now in trinity county it can be 110+ F at times... going from 500 feet to 3400 feet in steep grades at times. Having the other persons comment is normal every day there so to speak. Not that they live there, just a valid point.
 

TheRaven

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Most don't see knock as an issue. When computer will retard timing accordingly. Ethanol hides knock and having a rich fuel mixture as well.
Ethanol can't "hide" knock. It's no different in that respect than any octane of pure gasoline. The engine controller will detect any pre-detonation of any kind regardless of ethanol content.
 

NWJeepr

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Most don't see knock as an issue. When computer will retard timing accordingly. Ethanol hides knock and having a rich fuel mixture as well.

Under load and heat... mountain trails and also towing will cause ping with 87. It's a no brainer!

Giving gas to add to the issue of lacking power, can be detrimental.

I had a discussion about turbo 4 cyl. When someone brought up the Alpha Romeo engine. Supposedly the same inside the Jeep.

They had no clue as to the issues with the engine until I posted my reply. The issue is fuel in oil contamination. Due to the fact. The turbo 4 cyl has direct injection the type of system has a flat with fuel leaking through the cylinders. It cut down oil life in half. The band aid was to replace oil pan with a 6 quart pan. So standard oil replacement routine is not affected.

Not that all engines have this issue, but bad burn and over compensation with throttle can allow gas to leak past cylinders to contaminate oil. More likely to happen with higher milage engines.

It's not the Ethanol directly doing damage, it's how inefficient the burn cycle effects oil. Cleaner burn better oil life, less wear. As for ping and heat they can cause damage and most are unaware what's happening as computer and low grade gas try and hide the issue.

Like I said... flat landers won't be effected as much.

Now in trinity county it can be 110+ F at times... going from 500 feet to 3400 feet in steep grades at times. Having the other persons comment is normal every day there so to speak. Not that they live there, just a valid point.
The Jeep 2.0 is similar but not exactly the same as the Alfa 2.0. It's a global engine used in various models with a few differences.

The sump capacity in the Jeep 2.0 is 5.0 quarts. And that speaks more to cooling capacity than it does any issues with fuel dilution.

Direct injection has been around in mass production for 30+ years and the early issues have nearly vanished, and most Jeep 2.0 owners aren't having any issues with excessive fuel dilution or top-end deposits.

I'm as equally confused about your statement regarding how "burn cycle" of the 2.0 affects oil. Direct Injection is actually a more complete burn than sequential or port injection.

How does any of this concern ethanol, again?
 

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roaniecowpony

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roaniecowpony

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I run 85 in my 3.6 no issues. I also live at 8000 feet elevation, routinely go to 11-12K feet and flat tow broken broncos out of the woods for my towing business.
At 8000 ft elevation, you have about 3/4 of the sea level rated horsepower. At 11-12k feet, it is down to less than 2/3 of the sea level rated power. So, cylinder pressure is much lower than maximum sea level power, and the result is that the probability of detonation is drastically reduced.
 

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At 8000 ft elevation, you have about 3/4 of the sea level rated horsepower. At 11-12k feet, it is down to less than 2/3 of the sea level rated power. So, cylinder pressure is much lower than maximum sea level power, and the result is that the probability of detonation is drastically reduced.
I'm aware of the difference altitude makes. I'm just over here laughing at the idea that 89 octane improves gas mileage.
 

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Just saw this over the weekend.



Lots of "Myths" busted about octane.
Are they tho? They even throw all the normal caveats in there of "In real world conditions with more load/heat I would never run 87" "This isnt boosted or high compression" Really all they did was show that a standard low compression engine under perfect ideal conditions will run just find on 87.
 

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TheRaven

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I run 85 in my 3.6 no issues. I also live at 8000 feet elevation, routinely go to 11-12K feet and flat tow broken broncos out of the woods for my towing business.
LOL there are a lot of guys here that will attack you for making this claim. I tried to explain this to them but they essentially accused me of witchcraft and tried to burn me at the stake.
 

roaniecowpony

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I'm aware of the difference altitude makes. I'm just over here laughing at the idea that 89 octane improves gas mileage.
Well, there's some possibility of that. If the engine can run more spark lead, it can potentially get more power from the same fuel charge.... or more mpg.
 

roaniecowpony

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LOL there are a lot of guys here that will attack you for making this claim. I tried to explain this to them but they essentially accused me of witchcraft and tried to burn me at the stake.
The raven is the symbol of witchcraft.
 

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roaniecowpony

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