Investigating Low Speed Pre-Ignition

[buster]

Link

Quote:
When the fuel is injected directly into the combustion chamber, it dilutes the oil film lining the cylinder. This fuel dilution reduces the surface tension and viscosity of the oil, causing an oil-fuel mixture to accumulate in the upper reaches of the piston top land crevice. The mechanical energy of the upstroke during compression pushes droplets into the combustion chamber, where they vaporise and can auto-ignite prior to spark ignition.

 

[Blueskies123]

Hopefully they have this problem fixed by the time I buy a one liter engine.

 

[Shannow]

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3625454/CaSa_contributing_to_LSPI_-_Tu

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3155033/Compression_Ignition_Gasoline_

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3489453/Re:_Why_all_the_fuss_over_NOAC#Post3489453

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3618838/Re:_Castrol_EDGE_0w20_-_4,892m#Post3618838

 

[Eddie]

Interesting that the Mazda SkyActiv DI Gas engine, injects fuel into a "cup" shapped indent in the center of the piston. Ed

 

[Virtus_Probi]

Interesting and incredibly long discussion on a Veloster Turbo forum...
http://www.velosterturbo.org/forum/velos...html#post275951

 

[Shannow]

Originally Posted By: Blueskies123
Hopefully they have this problem fixed by the time I buy a one liter engine.


I'm thinking that first they have to man up and accept that 1qt/1,000 milesis not, and has never been an acceptable level of oil consumption.

After that dream is fulfilled, they can get the AW additives back to the point that they no longer have to protect the cat at 1qt/1,000 miles.

 

[SwampSurvivor]

That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.

 

[cashmoney]

Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.



Wow - there's a blast from the past - blame EPA for some car companies' bad engine designs. This is the same kind of statements some people made in 1975 and 1985 about EPA's impossible extreme mpg and clean emission goals. Pure unadulterated horse poop.

 

[buster]

Originally Posted By: Shannow

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3625454/CaSa_contributing_to_LSPI_-_Tu

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3155033/Compression_Ignition_Gasoline_

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3489453/Re:_Why_all_the_fuss_over_NOAC#Post3489453

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3618838/Re:_Castrol_EDGE_0w20_-_4,892m#Post3618838


thank you.

 

[eljefino]

Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.


They could also cut 500 lbs of bluetooth doohickeys and makeup cameras to meet the same mileage goals with regular tension rings.

 

[4wheeldog]

Originally Posted By: eljefino
Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.


They could also cut 500 lbs of bluetooth doohickeys and makeup cameras to meet the same mileage goals with regular tension rings.


The EPA does not require low tension rings, or XW/20 oil. Manufacturers choose to use those technologies to meet the mileage goal. Sometimes, a bean cutter finds a way to save a nickel, and the product suffers all out of proportion to the savings.

Clearly, low tension rings and 20 weight oil can work without excessive consumption, because most engines using those things do just fine.

When they don't work, blame the manufacturer for cutting corner.......The EPA may set goals, but the manufacturers choose how to meet them.

 

[SwampSurvivor]

Originally Posted By: 4wheeldog

When they don't work, blame the manufacturer for cutting corner.......The EPA may set goals, but the manufacturers choose how to meet them.


That's the point I was trying to make.

 

[CT8]

Originally Posted By: eljefino
Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.


They could also cut 500 lbs of bluetooth doohickeys and makeup cameras to meet the same mileage goals with regular tension rings.
NO WAY !!! [I am a fuddy duddy I thing the connect stuff sucks]

 

[A_Harman]

Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.


The tight tolerances are possible, it's just the cost of meeting them. The tolerances that are held in production now would make you say "impossible" if you were to look at a set of drawings for pistons and rings. The next step being pushed by future CAFE standards is even crazier.

 

[A_Harman]

Originally Posted By: Eddie
Interesting that the Mazda SkyActiv DI Gas engine, injects fuel into a "cup" shapped indent in the center of the piston. Ed


That's standard stuff in everybody's GDI engines.

 

[A_Harman]

Originally Posted By: Blueskies123
Hopefully they have this problem fixed by the time I buy a one liter engine.


The infernal regions will freeze over before I buy a one liter engine.

 

[HerrStig]

Originally Posted By: cashmoney
Originally Posted By: Miller88
That isn't going to happen until the EPA backs off a bit and stops forcing companies into taking extreme fuel savings measures (low tension piston rings) that cause oil consumption. Or, manufacturers need to step up their game and have better manufacturing tolerances that can handle these things without drinking oil.



Wow - there's a blast from the past - blame EPA for some car companies' bad engine designs. This is the same kind of statements some people made in 1975 and 1985 about EPA's impossible extreme mpg and clean emission goals. Pure unadulterated horse poop.
Yup, the EPA NEVER makes mistakes, such as MBTE trahing ground water and big yellow rivers. It's always "some other guy's fault" these days.

 

[SwampSurvivor]

According to EPA, which one of the below vehicles is a gross polluter and was forced out of production, and which one is a certified Low Emissions Vehicle (LEV)

Hint: The one that gets 55MPG is a gross polluter. The one that gets 9 is not.

 

[SilverC6]

The EPA remains out of control chasing a problem that has already been materially solved.

Now the law of diminishing returns kicks in and the result is 25% of the cost of your new vehicle is federal compliance.

Why not let the EPA be in charge of border security.

 

[440Magnum]

Interesting- that means that LSPI has the same root cause as the excessive fuel dilution and high unburned HC emission issues that DI engines seem to have.