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Heimkehr

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We can utterly trash these engines by putting the spark plug in the wrong place, but potentially also by simply using insufficient octane?
That's the question, John.

The more we know, the better informed our future purchase decisions will be.
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alphawolff

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Current consensus is these engines are suffering from extreme knock at 87 octane.

The vehicle legally needs to be able to run (i.e. function within emission requirements) on 87. Not really sure what their solution is going to be but this seems to be a widespread issue at the moment. Most are breaking within the first 200 miles, some right off the delivery truck. This seem very odd considering this engine would've undergone trial testing well before being put into service. I wonder if they changed something last minute or installed something improperly at the factory. It could also of been a PCM tuning issue with improper ignition timing.

Currently we're being required to replace all 8 plugs as a set and send pictures to corporate alongside the claim.

At the end of a day this is a turbo 4 banger making 324HP/330tq yoinking along a 3 ton vehicle. Even attempting to run 87 on it is ludicrous, but your average soccer mom is going to put the cheapest shit possible in it. Very curious to see what the final solution is.
 

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Current consensus is these engines are suffering from extreme knock at 87 octane.

The vehicle legally needs to be able to run (i.e. function within emission requirements) on 87. Not really sure what their solution is going to be but this seems to be a widespread issue at the moment. Most are breaking within the first 200 miles, some right off the delivery truck. This seem very odd considering this engine would've undergone trial testing well before being put into service. I wonder if they changed something last minute or installed something improperly at the factory. It could also of been a PCM tuning issue with improper ignition timing.

Currently we're being required to replace all 8 plugs as a set and send pictures to corporate alongside the claim.

At the end of a day this is a turbo 4 banger making 324HP/330tq yoinking along a 3 ton vehicle. Even attempting to run 87 on it is ludicrous, but your average soccer mom is going to put the cheapest shit possible in it. Very curious to see what the final solution is.
What typically has to be replaced, just the plugs?
 

2nd 392

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Current consensus is these engines are suffering from extreme knock at 87 octane.

The vehicle legally needs to be able to run (i.e. function within emission requirements) on 87. Not really sure what their solution is going to be but this seems to be a widespread issue at the moment. Most are breaking within the first 200 miles, some right off the delivery truck. This seem very odd considering this engine would've undergone trial testing well before being put into service. I wonder if they changed something last minute or installed something improperly at the factory. It could also of been a PCM tuning issue with improper ignition timing.

Currently we're being required to replace all 8 plugs as a set and send pictures to corporate alongside the claim.

At the end of a day this is a turbo 4 banger making 324HP/330tq yoinking along a 3 ton vehicle. Even attempting to run 87 on it is ludicrous, but your average soccer mom is going to put the cheapest shit possible in it. Very curious to see what the final solution is.
Interesting “legally” , is that because Stella didn’t want to make it 91 required and scaring potential customers off ? … So you replace the plugs, detonation kills them again running 87, they better figure it out quickly.
 

alphawolff

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What typically has to be replaced, just the plugs?
All eight plugs, and if the white porcelain or electrode is missing you have to replace the engine.


Interesting “legally” , is that because Stella didn’t want to make it 91 required and scaring potential customers off ? … So you replace the plugs, detonation kills them again running 87, they better figure it out quickly.
I'm hearing from other techs they indeed replace plugs and it comes back a few hundred miles later. And yeah, LEGALLY all road emissions compliant vehicles much MEET emission requirements at 87 octane. This means no misfiring.
 

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2nd 392

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All eight plugs, and if the white porcelain or electrode is missing you have to replace the engine.



I'm hearing from other techs they indeed replace plugs and it comes back a few hundred miles later. And yeah, LEGALLY all road emissions compliant vehicles much MEET emission requirements at 87 octane. This means no misfiring.
I’m still confused, 392’s 91 required. I’ll go out on a limb with Hellcat’s 91, also other performance vehicles.
 

alphawolff

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I’m still confused, 392’s 91 required. I’ll go out on a limb with Hellcat’s 91, also other performance vehicles.
You can run 87 in your 392 and it'll meet federal emission requirements. It might right like shit, but it'll still meet those requirements. It'll probably pull as much timing as it possibly can to make that happen.
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