LSPI questions

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Nov 26, 2019
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First post noob here but read lots over the years. I had a 335i that gave up the ghost a while back and trying to wrap my mind around a full boost bone dry compression stroke and some oil getting in there causing pre-ignition and my bearing failure ultimately. the car is gone.

Wondering if something about the Castro edge Euro synth formula was less prone to pre-ignition, like is it a higher octane that can take all that heat and a dry compression stroke?

Had a friend's Volvo his wife was driving down the highway normal speed and a couple of EcoBoost trucks I heard just burnt holes in the pistons and catastrophically ruined the engines like light bulbs.. Wondering if this is a specific engine issue or any new thoughts on these lspi problems? looking into maybe another direct injected vehicle and would rather be educated before I pick one. thanks
 
I believe the Castro’s Edge Euro oils are
all SN or SL rated.
Something rated SP or SN+ would be better
for preventing LSPI.
The non-euro Edge full synthetic oils have this rating.
 
LSPI doesn’t cause bearing failure, does it? I thought it caused immediate destruction of the piston. It either happens or it doesn’t.
I believe the problem is pre ignition and not detonation. I come from a 30-plus year history of riding the knock sensors and high-powered engines that burn plenty of oil but my n54 relationship was very very short.

in a heavy duty forged piston motor like the n54 that bats and eye at a little pre-ignition, pre ignition happens at bottom dead center which causes the eventual bearing failure instead of near top dead center like detonation.

I assumed the knock sensors worked like a regular engine but that is not the case LOL

just imagine if a little oil started getting in there from accumulated in the intercooler, PCV issue or just a leaky valve guide, that's where you get these burnt down engines without any notice but I have very little experience with direct injected motors so it's all speculation on my part

any input is appreciated but many people in record power go back to port injection and just plug off the DI injectors. I think I hate it
 
LSPI doesn’t cause bearing failure, does it? I thought it caused immediate destruction of the piston. It either happens or it doesn’t.

I think LSPI also puts excess shock loads into the rod and down in to the bearing. Remember, it happens at "low speed" (the "LS" part of LSPI) when the engine RPM is low and the MOFT is lower, so there is more chance of bearing metal-to-metal contact.
 
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N54 had numerous issues, but not LSPI. Except old VW 1.4 T/SC engine, Euro turbo's are design very well to counter this.
Except for my Oktoberfest built Tiguan. That died of LSPI.

I didn't take pictures of my piston #2, but it looks like the picture on the right
piston-damage-caused-by-LSPI.jpg
 
I believe the problem is pre ignition and not detonation. I come from a 30-plus year history of riding the knock sensors and high-powered engines that burn plenty of oil but my n54 relationship was very very short.

in a heavy duty forged piston motor like the n54 that bats and eye at a little pre-ignition, pre ignition happens at bottom dead center which causes the eventual bearing failure instead of near top dead center like detonation.

I assumed the knock sensors worked like a regular engine but that is not the case LOL

just imagine if a little oil started getting in there from accumulated in the intercooler, PCV issue or just a leaky valve guide, that's where you get these burnt down engines without any notice but I have very little experience with direct injected motors so it's all speculation on my part

any input is appreciated but many people in record power go back to port injection and just plug off the DI injectors. I think I hate it
 
“pre ignition happens at bottom dead center”???
NO Way! How can any ignition happen then when compression hasn’t even started and on a direct ignition car ZERO fuel has been injected into the cylinder? You just have a cylinder full of boost pressure air and you get “pre ignition“?
 

 
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With LSPI pressure spikes inside the cylinder that are 3 to 4 times as high as normal combustion events, more than just piston damage can occur.
 
interesting those cracked Pistons I've seen countless times look like detonation to me. melted Pistons look like pre-ignition to me. on Volkswagen motors I've boosted I've even seen some that had pre-ignition without any cracks, something happened to the fuel supply and the boost was low and they never let off the gas so it didn't have enough to crack the ring lands I suppose but it did go into pre-ignition to melt
 
and air will burn much hotter than mixture I'm sure we all know.

wide open throttle or low speed, it seems after a little more searching the problem is anything that ends up in that dry compression stroke causes pre-ignition low speed or wide open throttle. these forged motors like the n54 aren't going to burn the Pistons real easy but they will crush the rod bearings.

I got on here thinking the octane of the oil was a factor LOL and now I'm realizing it's carbon particles maybe some oil vapor, maybe a gnat got through the air filter. how many light pre-ignition hits can a motor take before it starts wearing through the bearing

it's just some thoughts, I don't have a direct injected motor at the moment. to try to get triple na horsepower out of for 300K miles like I've seen done..
 
Except for my Oktoberfest built Tiguan. That died of LSPI.

I didn't take pictures of my piston #2, but it looks like the picture on the right
piston-damage-caused-by-LSPI.jpg
did you happen to have a port injection on this n54 failure?? I just think of preignition as a slow crushing pressure and detonation more like a hammer.
 
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