The truth about oil change intervals and analysis

[4WD]

While that is true, at the same time Lake often says things that are not quite true. A recent video where he's talking about M1 0w40, he says the FS on the label means full synthetic but yet it actually stands for FULL SAPS. Big difference there. And in this video in question when they are talking about how the manufacturers are calling for longer oil change intervals being extended and all that needs to happen is for the engine to just get past the warranty period, that's total nonsense too. No manufacturer in their right mind would want their engines to be dying just shortly after the warranty is up. Nobody would buy their cars anymore. There are a few manufacturers out there whose reputation was built on having long lasting engines (Toyota, Honda, Volvo) and there is no way they want to sully that reputation with a bunch of dead engines.

Lake does have a lot of oil knowledge, but it's very odd that with all of his oil analysis expertise he still says that we need to do shorter oil change intervals. The data he's looking at on a daily basis proves otherwise.

So did the kid in purple high tops at the call center - maybe he called there first

 

[scalar_field]

kind of wild that some people think 3,000 mile OCIs are a "takeaway" of this video. Lake Speed, Jr., while being diplomatic, very clearly communicates that he doesn't subscribe to that approach.

 

[OVERKILL]

No. OEM tunes are generally not setup for more fueling when spark knock is detected. If anyone wants to prove otherwise, they should post the tables from the ECU software. Otherwise, it is speculation at best.

High load operating points (blue triangles and green squares in the high load region in Figure 5) are defined in this paper as the region where enrichment is observed. In this region, data cannot be collected with steady-state procedures due to the transient nature of the engine control, which is employed to protect the engine from excessively high temperatures, to avoid pre-ignition at low speed/high load, or to avoid knock at high speed/high load. The ECU avoids these damaging effects by transiently adjusting the engine control parameters, often at the expense of fuel consumption and efficiency, through control techniques such as spark retard and fuel enrichment.

When operating in high load conditions, the engine ECU controls several parameters such as A/F ratio and spark timing differently depending upon speed and load on the upper limits of the engine performance. Generally, engines operate at a stable stoichiometric A/F ratio from idle to approximately 70% load. Above 70% load, the engine ECU will transition the A/F ratio from stoichiometric to enriched as needed to protect the engine from excessive heat, pre- ignition and knock.

And you can see it varying fuel flow while spark timing is relatively static:

From here: Benchmarking a 2016 Honda Civic 1.5-liter L15B7 Turbocharged Engine and Evaluating the Future Efficiency Potential of Turbocharged Engines - PMC (nih.gov)

Unfortunately, the testing they did was almost all on 87 octane fuel. They did some testing with Tier 3 (91 octane) but didn't do any high load testing, only tracking Brake Thermal Efficiency, which shows a difference but it's not as valuable as having say the same graph as above but on 91 octane.

 

[4WD]

3k oil changes are a complete waste. I wish Jr. at least made the claim that 7.5 oil changes are harmless with good oil. These guys pushing the early change. all good and that but totally unnecessary. Engine that cause fuel dilution maybe a 5k change

Yeah - he talked about UOA’s - but apparently decided not to enter that debate over the 3k thing - think customers need to take that up with the builder directly … Lake did plug GM’s OLM and we know that will get you between 6000-7500 FWIW …

 

[4WD]

3,000 miles is not science, it's literally the antithesis of science because it's predicated on absolutely no operating data.

Or just a dude that does not want to pay warranty claims and has YOU pay his insurance

 

[Pablo]

And you can see it varying fuel flow while spark timing is relatively static:
View attachment 211216

From here: Benchmarking a 2016 Honda Civic 1.5-liter L15B7 Turbocharged Engine and Evaluating the Future Efficiency Potential of Turbocharged Engines - PMC (nih.gov)

Unfortunately, the testing they did was almost all on 87 octane fuel. They did some testing with Tier 3 (91 octane) but didn't do any high load testing, only tracking Brake Thermal Efficiency, which shows a difference but it's not as valuable as having say the same graph as above but on 91 octane.

Thanks. Touched on here as well: https://www.hpacademy.com/technical-articles/how-to-tune-a-turbocharged-engine/

"As we combust more fuel and air in the cylinder, we end up creating more heat. We need to be mindful of this heat or we risk damaging our engine or creating conditions where knock is more likely to occur. While it might sound a little counter-intuitive, adding a little extra fuel by way of a richer air-fuel ratio target will mean that some of the additional fuel will pass through the combustion chamber unburned, and this will have the effect of cooling our combustion charge temperature..."

 

[CarbonSteel]

If you have LSPI, you are probably only going to have it once. It tends to be devastating, which is why there has been so much work put in to avoiding it entirely. On the other hand, conventional pinging/spark knock, which is why engines have knock sensors, is controlled through ignition timing of course, but also through enrichment and injection timing with GDI. This is particularly true for TGDI engines where enrichment and injector timing enable compression ratios that aren't possible with port injection, let alone on regular fuel. If the amount of enrichment and injector timing can be influenced through using higher octane, using feedback from the knock sensor, then this can have a positive effect on reducing the amount of fuel that makes its way into the sump.

I agree in principle, but I run premium as do others and still have fuel dilution. Color me skeptical higher octane gasoline has any negligible impact on fuel dilution in engines which are susceptible to it.

Diesel engines tend to disprove that theory.

 

[Pablo]

I agree in principle, but I run premium as do others and still have fuel dilution. Color me skeptical higher octane gasoline has any negligible impact on fuel dilution in engines which are susceptible to it.

Diesel engines tend to disprove that theory.

Turbo?

Does your engine get better MPG with premium?

 

[OVERKILL]

I agree in principle, but I run premium as do others and still have fuel dilution. Color me skeptical higher octane gasoline has any negligible impact on fuel dilution in engines which are susceptible to it.

It would only make a difference where enrichment is a variable based on feedback. If your engine just goes "we are at 80% load, increase enrichment to predetermined level in table" then yeah, you aren't going to see a difference. It will depend on engine design and ECM programming.

 

[CarbonSteel]

Not necessarily, only if knock detected - which happens under the high load (high pressure) situations with lower rated fuels.

Huh? If "turbo engines under load typically map richer, especially normally lean burn turbos", then octane would be irrelevant. Confused as to why it is "both ways".

With that said, anyone running a TGDI consistently experiencing spark knock clearly needs to be running a different octane level anyway.

In the end, I UOA to monitor fuel dilution and have increased my 100C cSt viscosity as a consequence and now don't worry about it since the oil remains in viscosity during its run.

 

[CarbonSteel]

Turbo?

Does your engine get better MPG with premium?

Twin turbo and yes, it not only gets better MPG, but also produces more HP. The EcoBoost engines is definitely able to take advantage of premium fuel.

 

[JTK]

I don't know why our peanut gallery of experts have their panties in a bunch over this. Mr. Speed clearly said at ~28:40 that the only way to know YOUR specific oil change interval is based on UOA data.

Some of us choose to spend $40 on a UOA (or what ever it is today) and some of us choose to use that money to change oil earlier than the manufacturer recommends.

 

[OVERKILL]

I don't know why our peanut gallery of experts have their panties in a bunch over this. Mr. Speed clearly said at ~28:40 that the only way to know YOUR specific oil change interval is based on UOA data.

Some of us choose to spend $40 on a UOA (or what ever it is today) and some of us choose to use that money to change oil earlier than the manufacturer recommends.

Pretty sure you can chalk that up to most people reacting to the OP's conclusion, not from actually watching the video:

 

[CarbonSteel]

It would only make a difference where enrichment is a variable based on feedback. If your engine just goes "we are at 80% load, increase enrichment to predetermined level in table" then yeah, you aren't going to see a difference. It will depend on engine design and ECM programming.

Agree, but again, octane would not play a role in this to any large degree.

 

[Sumboodie]

I don't know why our peanut gallery of experts have their panties in a bunch over this. Mr. Speed clearly said at ~28:40 that the only way to know YOUR specific oil change interval is based on UOA data.

Some of us choose to spend $40 on a UOA (or what ever it is today) and some of us choose to use that money to change oil earlier than the manufacturer recommends.

$40?

It's about $20.00 through Chevron. I think CAT SOS is about the same too.

 

[The Critic]

And you can see it varying fuel flow while spark timing is relatively static:
View attachment 211216

From here: Benchmarking a 2016 Honda Civic 1.5-liter L15B7 Turbocharged Engine and Evaluating the Future Efficiency Potential of Turbocharged Engines - PMC (nih.gov)

Unfortunately, the testing they did was almost all on 87 octane fuel. They did some testing with Tier 3 (91 octane) but didn't do any high load testing, only tracking Brake Thermal Efficiency, which shows a difference but it's not as valuable as having say the same graph as above but on 91 octane.

Fueling varies with load, that is fundamental. I don’t see anything here that indicates spark knock to be the sole trigger of fueling enrichment.

 

[ATex7239]

Grows up whole life around racing, engines and oil.
Becomes a crew member on professional racing team.
Becomes certified in tribology.
Becomes head of R & D for oil on famous racing team.
Develops and blends oil for famous racing team.
Starts an independent oil analysis business.
Starts an oil related YT channel.
Makes YT video and talks about oil.

Some guy in comments “Pssh, BS…”

 

[OVERKILL]

Agree, but again, octane would not play a role in this to any large degree.

It would if it's using knock sensor feedback to drive the level of enrichment, which seems to be implied with the Honda strategy with the use of the terms/statements "transiently" and "enrich as needed".

 

[Astro14]

3k oil changes are a complete waste. I wish Jr. at least made the claim that 7.5 oil changes are harmless with good oil. These guys pushing the early change. all good and that but totally unnecessary. Engine that cause fuel dilution maybe a 5k change

I agree.

And I wouldn’t worry too much about what @atikovi says, once you read through some of his “decisions” over the years, you’ll understand.

 

[OVERKILL]

Fueling varies with load, that is fundamental. I don’t see anything here that indicates spark knock to be the sole trigger of fueling enrichment.

Not the sole trigger, but the enrichment employed here is obviously not static, they are varying the amount of enrichment, as can be seen by the lambda and fuelling data for a fixed amount of load, which means it's a feedback-driven system, and it's doing it while spark stays relatively static. Interestingly, in the middle of the sustained high load area, the ECM pulls a bit of spark, and then ramps it back up, and during this reaction, the fuelling/enrichment becomes static, then as spark flattens again, fuelling is varied again, so it seems to be two strategies used together.