Dex1Gen3 performance observations

[twX]

How is “regular knock” and pre-ignition knock different?

In both cases, the air-fuel mixture spontaneously ignites. In the case of regular knock, or spark knock, this occurs after the spark plug has already fired, but it occurs in an area beyond the normal flame front of the spark-ignited combustion, which results in multiple flame fronts and can cause shock waves. This causes a modest increase in peak cylinder pressures, and can cause piston erosion at higher engine loads, but does not cause catastrophic damage in a short time.

Low speed pre-ignition, or LSPI, occurs before the spark plug fires. Peak pressures from LSPI tend to get a lot higher than they do from spark knock and it is much more damaging. There is also a tendency for LSPI events to occur one after the other for several combustion cycles. Sometimes a single series of LSPI events can destroy an engine.

On modern engines, spark knock won't usually be audible due to the engine's knock control, while LSPI can be quite loud.

 

[Alain2]

In both cases, the air-fuel mixture spontaneously ignites. In the case of regular knock, or spark knock, this occurs after the spark plug has already fired, but it occurs in an area beyond the normal flame front of the spark-ignited combustion, which results in multiple flame fronts and can cause shock waves.

They are both pre ignition issues, before spark.

 

[Alain2]

Interesting, that's quite sophisticated and nearly in the realm of research papers. Not an easy thing to do.

What kind of sensors do you use and how do you analyze the data?

Regular knock sensors can detect lspi, but not always as they present different frequency. I was using HP Tuners software with all the OEM functions sensors such as engine temp, engine speed, knock sensors, ait, boost pressure, fuel table, timing table, boost enrichment, temp enrichment, I also had external input with CHT, egt and af sensors.

Nothing scientific, just for fun.

 

[Alain2]

When their feet are put to the fire people seemingly just disappear. Alain2 est tu a l'écoute ?

I was enjoying my motorcycle, it is nice outside, you should try it!

 

[Alain2]

E

Especially when it shows they’ve logged in during the meantime.

Now you can say you data logged something.

 

[ARCOgraphite]

Why do I get the feeling I am watching "The Three Faces of Eve"?
Bizarre thread.

 

[Alain2]

I was only here to question Kschachn on why he is certain that no LSPI could be experienced by the OP.

 

[ARCOgraphite]

I was only here to question Kschachn on why he is certain that no LSPI could be experienced by the OP.

I did not see a specific vehicle nor the engine nor lubricant or conditions of the "LSPI" event.

We have had heretofore the antithesis of TMI

Knock or Spark knock occurs after the ignition event. Commonly caused by early spark timing for the presented loading and can be exacerbated by certain deleterious CC conditions and hot spots distal from the ignition flamefront.

 

[Alain2]

Bro is pleading insanity here…

 

[Nesterenko]

I was enjoying my motorcycle, it is nice outside, you should try it!

Business before pleasure. Apparently yours is unfinished.

 

[SubieRubyRoo]

Bro is pleading insanity here…

I don’t think many here would argue on your self-diagnosis.

It’s beyond a stretch of belief to listen to you casually say you’ve experienced LSPI while datalogging, when car manufacturers and oil blenders are showing pictures of disintegrated pistons, and bent rods, and other catastrophic failures from LSPI.

You speak of LSPI like you got a little bit of condensation coming out your exhaust on startup, but LSPI is more like blowing a tire on the highway because you drove over your crankshaft. In the relatively rare occasions where it has happened, the destruction is hardly short of impressive.

 

[ZeeOSix]

LSPI can happen without catastrophic engine damage. Depends on the level of LSPI.
https://www.stle.org/files/TLTArchi... event that,events are random and infrequent.

 

[ZeeOSix]

Engineering Explained on LSPI.

 

[Nmr1981]

Tastes the same to me…Coke, New Coke…dexos