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Discussion Starter · #1 ·
Has anyone exclusively run 87 octane gasoline in their 2.0 GDI? If so, have you "blown" the engine due to 87 octane gasoline?
 

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huh?
87 octane is regular fuel...and it's designed for it...

Makes no sense [idea]
 

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Discussion Starter · #3 ·
huh?
87 octane is regular fuel...and it's designed for it...

Makes no sense [idea]
I'm not so sure about that. As I'm learning a boat load about engines in another thread, the 2.0 GDI has a compression ratio of 12.0 : 1 (or simply, 12.0).

A value of 12.0 puts the 2.0 GDI in the super-super car category and makes it, by the compression ratio alone, an ultra performance engine (or motor as some call it) by design.

To get a 12.0 compression ratio engine to even run on 87 octane gasoline takes enormous compromises and electronics against the performance design.

So to say the 2.0 GDI was designed to run on 87 octane is a misnomer. It was designed as an ultra performance naturally aspirated 2.0 four cylinder engine that Ford "compromised" to be economical.

It's that "compromising" to be economical that worries me that running 87 octane gasoline, even though Ford says it's "ok", is going to damage the engine. I've learned there's only so much you can do to get a 12.0 compression ratio engine to even run on anything less than 91 octane gasoline. And while Ford appears to have done it, the question is, how well did they do it, because it's nearly an impossible task from what I'm learning.

Am I slowly degrading my engine by running 87 octane gasoline as the fuel source? Should I expect it to grenade the engine within say 60k miles?
 

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Ford claims improved performance from premium fuels, but it is not required.

Claiming that 87 octane fuel will somehow ruin the engine is asinine. This is a MASS PRODUCED ECONOMY CAR.

Use your head.
 

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You're reading about port fuel injection.
GDI injects the fuel directly onto the piston cooling temperature in the cylinders preventing preignition.
12:1 on port injection with 87 octane would blow a hole in the piston. With GDI it's no problem. It's a great technology that enables more power out of the same fuel with no compromises.
 

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Discussion Starter · #6 ·
Ford claims improved performance from premium fuels, but it is not required.

Claiming that 87 octane fuel will somehow ruin the engine is asinine. This is a MASS PRODUCED ECONOMY CAR.

Use your head.
I'm trying. I understand the mass produced (and sold) part of it -- just like a decade plus of Focuses before the Mk3, but what on Earth was Ford thinking putting a 12.0 compression ratio in an economy car? Sorry, but 12.0 isn't an "economy" designed engine as I'm learning.
 

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I'm trying. I understand the mass produced (and sold) part of it -- just like a decade plus of Focuses before the Mk3, but what on Earth was Ford thinking putting a 12.0 compression ratio in an economy car? Sorry, but 12.0 isn't an "economy" designed engine as I'm learning.
All modern cars with GDI have 12:1 or greater compression (unless turbocharged)
 

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I'm not so sure about that. As I'm learning a boat load about engines in another thread, the 2.0 GDI has a compression ratio of 12.0 : 1 (or simply, 12.0).

A value of 12.0 puts the 2.0 GDI in the super-super car category and makes it, by the compression ratio alone, an ultra performance engine (or motor as some call it) by design.

To get a 12.0 compression ratio engine to even run on 87 octane gasoline takes enormous compromises and electronics against the performance design.

So to say the 2.0 GDI was designed to run on 87 octane is a misnomer. It was designed as an ultra performance naturally aspirated 2.0 four cylinder engine that Ford "compromised" to be economical.

It's that "compromising" to be economical that worries me that running 87 octane gasoline, even though Ford says it's "ok", is going to damage the engine. I've learned there's only so much you can do to get a 12.0 compression ratio engine to even run on anything less than 91 octane gasoline. And while Ford appears to have done it, the question is, how well did they do it, because it's nearly an impossible task from what I'm learning.

Am I slowly degrading my engine by running 87 octane gasoline as the fuel source? Should I expect it to grenade the engine within say 60k miles?
Now you're just being childish.

for the rest of you, his claims of supercar territory and the like are sarcasm, attributing that claim to me when i never actually made it in the first place.
 

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tooOld, your thinking in terms of older muscle cars...with those crs you would get detonation if you were running these compression ratios on low grade fuel. The designs of newer engines offset this. as stated direct inject engines are different as are materials of the heads. Even in the older engines switching to aluminum heads would allow you to increase compression and run lower octane than with cast heads. If they say it is safe for 87 octane....take it to the bank....not trying to insult you, but im sure the engineers know more about this than you, or most of us for that matter.
 

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Now you're just being childish.

for the rest of you, his claims of supercar territory and the like are sarcasm, attributing that claim to me when i never actually made it in the first place.
Wait...is this carry over from another thread? Have we been trolled?
 

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tooOld, your thinking in terms of older muscle cars...with those crs you would get detonation if you were running these compression ratios on low grade fuel. The designs of newer engines offset this. as stated direct inject engines are different as are materials of the heads. Even in the older engines switching to aluminum heads would allow you to increase compression and run lower octane than with cast heads. If they say it is safe for 87 octane....take it to the bank....not trying to insult you, but im sure the engineers know more about this than you, or most of us for that matter.
the aluminum heads alone are not what make this engine capable of running on 87 octane, albeit compromised and relatively inefficient.

TooOld...I never claimed it would "grenade the engine". Please stop making up claims.
 

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Discussion Starter · #12 ·
tooOld, your thinking in terms of older muscle cars...with those crs you would get detonation if you were running these compression ratios on low grade fuel. The designs of newer engines offset this. as stated direct inject engines are different as are materials of the heads. Even in the older engines switching to aluminum heads would allow you to increase compression and run lower octane than with cast heads. If they say it is safe for 87 octane....take it to the bank....not trying to insult you, but im sure the engineers know more about this than you, or most of us for that matter.
Ahh ok, thank you. I guess things have changed since the days of push rod, 2 valves per cylinder, carbureted engines.

If you think the engineers have a handle on it then I'll sleep better. And if you think running 87 octane gasoline won't harm my 2.0 GDI, then that makes me feel better too.
 

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All modern cars with GDI have 12:1 or greater compression (unless turbocharged)
qft.

Maybe 45 years ago you only got a high compression ratio in gas-guzzling performance engines that required high octane leaded fuels, but strangely enough, times have changed.

The SkyActive engines in Mazda's newer cars have a 13:1 ratio in the US and 14:1 in other countries. US models are tuned for 87 octane.
 

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To offer more serious replies to the troll OP:

While engine technologies have indeed improved, fuel technologies really have not, and Octane as a fuel metric has not changed at all. Octane has always been a measure of resistance to detonation. the physics has not changed, but the technology of an engine in preventing detonation has.

BUT TO PREVENT DETONATION THE ENGINE MUST RUN LESS EFFICIENTLY. That's the claim, and the ONLY claim, I'm making. And a less efficient tune on a motor built for and capable of taking advantage of higher octane fuel while running more efficiently is not going to result in equivalent or better fuel economy.
 

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Discussion Starter · #16 ·
the aluminum heads alone are not what make this engine capable of running on 87 octane, albeit compromised and relatively inefficient.

TooOld...I never claimed it would "grenade the engine". Please stop making up claims.
And I never claimed you claimed it would "grenade the engine." As part of my engine education (2.0 GDI actually), I'm just worried that the engineers didn't fully take into consideration of the use of 87 octane gasoline in a 12.0 compression engine. Hence it was a question.

But as others have stated, Ford engineers did take it into consideration and there's nothing to worry about.
 

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And I never claimed you claimed it would "grenade the engine." As part of my engine education (2.0 GDI actually), I'm just worried that the engineers didn't fully take into consideration of the use of 87 octane gasoline in a 12.0 compression engine. Hence it was a question.

But as others have stated, Ford engineers did take it into consideration and there's nothing to worry about.
All of these "super car" and "impossible" statements you're posting, as well as the thread title asking if you'd damage your engine are direct statements that you're implying I made in the other thread. Don't play like I'm stupid, and don't be a childish fool about it.

And playing innocent as to your intentions isn't helping your position either. I never said it was impossible to make a 12:1 compression engine (not 12.0...that's not a ratio, Mr. Engineer) run reliably on 87 octane. I will say it one last time: it will NOT RUN AS EFFICIENTLY. So no, there's nothing to "worry about". The discussion was not about engine damage, it was about fuel economy, and you know it. This strawman did nothing to advance the discussion at all.
 

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Not only that...... these ECU's are a lot smarter and will actually make timing and fuel adjustments based on the grade of fuel being run in the engine.

Anyone with a Di engine and a heads up display can easily monitor this as I found on my last 4000 km road trip. It was pretty much instantaneous. It only took 1km of driving at a constant speed for my ECU to make the adjustment to a higher fuel grade.

With my Skyactiv 2.0L Mazda I went from a range of 623km/tank @ 113km/hr on regular (89 oct) to a range of 730km/tank @ 113km/hr on premium (93 oct). Same day same temperatures and elevation.
 

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Discussion Starter · #19 ·
All of these "super car" and "impossible" statements you're posting, as well as the thread title asking if you'd damage your engine are direct statements that you're implying I made in the other thread. Don't play like I'm stupid, and don't be a childish fool about it.

And playing innocent as to your intentions isn't helping your position either. I never said it was impossible to make a 12:1 compression engine (not 12.0...that's not a ratio, Mr. Engineer) engine run reliably on 87 octane. I will say it one last time: it will NOT RUN AS EFFICIENTLY. So no, there's nothing to "worry about". The discussion was not about engine damage, it was about fuel economy, and you know it. This strawman did nothing to advance the discussion at all.
Run less efficiently than what? Than optimal? Than under detonation? I'm just trying to learn here, and you're getting all bent out of shape.
 
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