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Old 09-30-2020, 11:31 AM   #51
HOK
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The IAG directions clearly state to maximize engine breaking and have the engine in full vacuum situations as much as possible. The rpm Babying I believe is just to keep people reving too high in initial break in to avoid engines that are not well oiled when run for the first time.

It seems to me that no matter if you are hard breaking or babying break in as long as you are in full vacuum situations it will seat the rings ok... Also the dependencies seem to be vary like correct ring gaps, types of rings, machining, etc. . .
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Old 10-07-2020, 08:43 AM   #52
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For the motors I build, I usually do a hard break-in. If I'm adding cams, I break those in with a 10-min, 10-min, 10-min approach, revving between 2k-3k.

Lots of engine breaking initially and I stay out of boost. Adding too much boost too soon, whilst the rings are mating with the cylinder walls and you can end up causing uneven wear. This is because of hot spots on the cylinder wall due to the rings sealing up.

Within the first 5-10 miles though I start giving it 70% throttle, revving up to 6k and still engine braking.

By mile 25 I'm giving the motor full boost.

I think hard break-in is great, but it's not just "floor it the second you get on the road" :-) There's still some easing into it. Never have had any low compression issues on my cars either. Rings seal up great.
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Old 10-07-2020, 12:59 PM   #53
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Originally Posted by BeastianSTI View Post
For the motors I build, I usually do a hard break-in. If I'm adding cams, I break those in with a 10-min, 10-min, 10-min approach, revving between 2k-3k.

Lots of engine breaking initially and I stay out of boost. Adding too much boost too soon, whilst the rings are mating with the cylinder walls and you can end up causing uneven wear. This is because of hot spots on the cylinder wall due to the rings sealing up.

Within the first 5-10 miles though I start giving it 70% throttle, revving up to 6k and still engine braking.

By mile 25 I'm giving the motor full boost.

I think hard break-in is great, but it's not just "floor it the second you get on the road" :-) There's still some easing into it. Never have had any low compression issues on my cars either. Rings seal up great.
I think that's a pretty reasonable actually. In the end the goal is to use the fresh crosshatch to mate the rings to the cylinder wall.
Using short bursts of moderate combustion pressure followed by periods of heavy vacuum to draw oil (in atomized form) up to the cylinder walls.


In the end, this is the argument as old as time.
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Old 10-07-2020, 01:57 PM   #54
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Using short bursts of moderate combustion pressure followed by periods of heavy vacuum to draw oil (in atomized form) up to the cylinder walls.


In the end, this is the argument as old as time.
Only problem is diesel engines represent half of all engines, and the piston ring/cylinder wall/compression fundamentals are identical other than diesels generate multiple times the compression.

They also happen to be unthrottled so they generate zero vacuum. This would suggest maximizing vacuum during break in is not only not critical to a ring seal, but borders on meaningless.
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Old 10-07-2020, 04:29 PM   #55
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Only problem is diesel engines represent half of all engines, and the piston ring/cylinder wall/compression fundamentals are identical other than diesels generate multiple times the compression.

They also happen to be unthrottled so they generate zero vacuum. This would suggest maximizing vacuum during break in is not only not critical to a ring seal, but borders on meaningless.
Diesel engines produce vacuum, it's a function of the piston drawing in on the intake stroke. Not having a throttle butterfly certainly results in less restriction, and therefor lower idle vacuum. That's why many diesel engines run a vacuum pump.

But there is still vacuum in the cylinder on the intake stroke.
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Old 10-07-2020, 04:32 PM   #56
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Only problem is diesel engines represent half of all engines, and the piston ring/cylinder wall/compression fundamentals are identical other than diesels generate multiple times the compression.

They also happen to be unthrottled so they generate zero vacuum. This would suggest maximizing vacuum during break in is not only not critical to a ring seal, but borders on meaningless.
Sure, maybe not critical but I fail to see how your example proves its meaningless.

As I said, the argument as old as time.
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Old 10-08-2020, 07:25 AM   #57
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Diesel engines produce vacuum, it's a function of the piston drawing in on the intake stroke. Not having a throttle butterfly certainly results in less restriction, and therefor lower idle vacuum. That's why many diesel engines run a vacuum pump.

But there is still vacuum in the cylinder on the intake stroke.
No they don't. That's the whole point.
Not having a throttle does not result in LESS vacuum, it results in NO vacuum. Get a diesel and put a gage on the intake, it will show zero vacuum.
They have vacuum pumps for that exact reason. The engine can't generate any vacuum so if accessories need vacuum they put a pump in to create it.

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Originally Posted by JSR84 View Post
Sure, maybe not critical but I fail to see how your example proves its meaningless.

As I said, the argument as old as time.
Isn't it clear as day? One engine generates zero vacuum and the break in works fine. Kind of suggests it is meaningless.
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Old 10-08-2020, 09:33 AM   #58
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No they don't. That's the whole point.
Not having a throttle does not result in LESS vacuum, it results in NO vacuum. Get a diesel and put a gage on the intake, it will show zero vacuum.
They have vacuum pumps for that exact reason. The engine can't generate any vacuum so if accessories need vacuum they put a pump in to create it.



Isn't it clear as day? One engine generates zero vacuum and the break in works fine. Kind of suggests it is meaningless.
I guess it just has open valves all the time too so the lack of throttle can actually provide atmospheric pressure all the way to the piston face

JFC dude, give it a break. The ring package on a diesel is kinda different than the ring package we run in an EJ. Literally different strokes for different folks.
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Old 10-08-2020, 10:21 AM   #59
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No they don't. That's the whole point.
Not having a throttle does not result in LESS vacuum, it results in NO vacuum. Get a diesel and put a gage on the intake, it will show zero vacuum.
They have vacuum pumps for that exact reason. The engine can't generate any vacuum so if accessories need vacuum they put a pump in to create it.



Isn't it clear as day? One engine generates zero vacuum and the break in works fine. Kind of suggests it is meaningless.
No man, you logic is flawed. Just because one engine operates in a different way doesn't negated the benefits of the way another engine operates. The cross hatch acts as an abrasive surface, knocking down all the high spots on the rings so they have a profile that closely matches the cylinder wall. I can take an abrasive and smooth a surface regardless if it's dry, lightly lubricant or heavily lubricant, but the oiled surfaces are going to create a better product, that takes less time and generates less heat.

Was the oil a critical factor? No, but it definitely provided a benefit and was not "meaningless"
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Old 10-08-2020, 10:32 AM   #60
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I guess it just has open valves all the time too so the lack of throttle can actually provide atmospheric pressure all the way to the piston face

JFC dude, give it a break. The ring package on a diesel is kinda different than the ring package we run in an EJ. Literally different strokes for different folks.
^no clue where you are even going with this
I said diesels don't generate vacuum and all of a sudden that is now up for debate?????
really????

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No man, you logic is flawed. Just because one engine operates in a different way doesn't negated the benefits of the way another engine operates. The cross hatch acts as an abrasive surface, knocking down all the high spots on the rings so they have a profile that closely matches the cylinder wall. I can take an abrasive and smooth a surface regardless if it's dry, lightly lubricant or heavily lubricant, but the oiled surfaces are going to create a better product, that takes less time and generates less heat.

Was the oil a critical factor? No, but it definitely provided a benefit and was not "meaningless"
I made a point about engine braking and needing vacuum to get a piston seal despite diesels not having vacuum and it working fine.
Now you are talking about cross hatching???
yes, I agree with everything you stated above. I didn't say anything about cross hatching or oil.
I said diesels don't pull vacuum, which is true.
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Old 10-08-2020, 10:54 AM   #61
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^no clue where you are even going with this
I said diesels don't generate vacuum and all of a sudden that is now up for debate?????
really????



I made a point about engine braking and needing vacuum to get a piston seal despite diesels not having vacuum and it working fine.
Now you are talking about cross hatching???
yes, I agree with everything you stated above. I didn't say anything about cross hatching or oil.
I said diesels don't pull vacuum, which is true.
Diesels don't pull vacuum until you get past the intake valve. Once into the cylinder, they do. Off throttle, on the intake stroke the cylinder is still pulling vacuum so the intake charge is actually pulled into the cylinder. It's not as much vacuum as pulling against a throttle plate, but it's still vacuum. And as stated, the ring package is considerably different on a diesel vs a gas ICE.

I think it's time to let this thread die.
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Old 10-08-2020, 11:46 AM   #62
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Diesels don't pull vacuum until you get past the intake valve. Once into the cylinder, they do. Off throttle, on the intake stroke the cylinder is still pulling vacuum so the intake charge is actually pulled into the cylinder. It's not as much vacuum as pulling against a throttle plate, but it's still vacuum.
^this is an unbelievable reach of all reaches ok

I understand the fundamental that you are reaching for but the entire design is to ramp that valve open as quick and far as possible and get as much air in as possible, period. That is the design goal and it works great.
If you measured the vacuum you are describing it would be a tenth of a psi.

You are essentially making the argument that an NA gas engine also pulls vacuum at WOT. Right, technically flow cannot be perfect so yes, it is probably pulling 0.1psi or maybe 0.05psi at WOT. But nobody calls that vacuum because that would be ridiculous.

so like I said, diesels don't generate vacuum. If vacuum was necessary for a ring seal no diesels would work. . . . .but alas they do
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Old 10-08-2020, 12:16 PM   #63
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^no clue where you are even going with this
I said diesels don't generate vacuum and all of a sudden that is now up for debate?????
really????



I made a point about engine braking and needing vacuum to get a piston seal despite diesels not having vacuum and it working fine.
Now you are talking about cross hatching???
yes, I agree with everything you stated above. I didn't say anything about cross hatching or oil.
I said diesels don't pull vacuum, which is true.
You used diesels as an example to prove your point that vacuum doesn't matter when bedding in rings. I was using another example to to prove how I believe its flawed logic.

As I said, its the argument as old as time. I have a feeling you're not going to change your mind.
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Old 10-08-2020, 12:26 PM   #64
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As I said, its the argument as old as time. I have a feeling you're not going to change your mind.
what argument is as old as time? Or as old as ICE engines?
that you need vacuum for a break in?

ok, I hear the argument. That's why I said why don't diesels need that then?

nobody can ever answer that
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Old 10-08-2020, 12:38 PM   #65
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So what draws air into a NA engine at WOT? momentum?

Air has mass, it doesn't flow into an engine just because a valve is open. It requires a differential pressure to motivate it. If a throttle is opened large enough to support the airflow demanded by the cylinders then there will be no measurable gage vacuum in the manifold. The expansion of the cylinder volume during the intake stroke is the vacuum source that draws air into the engine.

Turn your question on it's head and ask why gasoline engines don't have particulate filters?
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Old 10-08-2020, 02:08 PM   #66
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So what draws air into a NA engine at WOT? momentum?

Air has mass, it doesn't flow into an engine just because a valve is open. It requires a differential pressure to motivate it. If a throttle is opened large enough to support the airflow demanded by the cylinders then there will be no measurable gage vacuum in the manifold. The expansion of the cylinder volume during the intake stroke is the vacuum source that draws air into the engine.

Turn your question on it's head and ask why gasoline engines don't have particulate filters?
agree with everything you said.
The design puts as little restriction as possible, making essentially no vacuum like I said. A fraction of a pound at most. Same reason and NA motor goes to zero vacuum at WOT.

No clue whatsoever what you are talking about regarding a particulate filter for diesel exhaust in this context.
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Old 10-13-2020, 02:40 PM   #67
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No they don't. That's the whole point.
Not having a throttle does not result in LESS vacuum, it results in NO vacuum. Get a diesel and put a gage on the intake, it will show zero vacuum.
They have vacuum pumps for that exact reason. The engine can't generate any vacuum so if accessories need vacuum they put a pump in to create it
DISCLAIMER: I'm just here for the diesel talk...

My employer manufactures diesel engines. Just to be sure I wasn't talking out my booty, I poked my head over the digital cubicle wall and asked a powertrain engineer if diesel engines create vacuum.

Their answer:

"Yes, the same vacuum they produce when NOT engine braking, but it's unusually not enough to run a brake booster, which is why diesel cars often add vacuum pumps."

Vacuum is measured in inches of mercury (in. Hg). PSI is a unit of pressure for positive readings.
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Old 10-13-2020, 03:35 PM   #68
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Their answer:

"Yes, the same vacuum they produce when NOT engine braking, but it's unusually not enough to run a brake booster, which is why diesel cars often add vacuum pumps."

Vacuum is measured in inches of mercury (in. Hg). PSI is a unit of pressure for positive readings.
For one, my stinking STI uses psi for it's vacuum gage. Either can be used. The vacuum a car generates is still a positive pressure, it's just lower than atmospheric. You could use pascals if you wanted.

Second, maybe a follow up question or two is in order. For starters, what the heck does it mean to say yes, the same vacuum when NOT engine braking?
Then I'd ask, how is vacuum produced considering they are un throttled.
Then, how much vacuum are you talking?

Because let's think this through for a minute. A diesel engine is a compression ignition engine. The whole reason they need 20:1 compression is to generate enough heat to ignite fuel on contact. If it was generating vacuum that would directly mean it's dynamic compression ratio would be something less than it's designed value of say 20:1. That would be the opposite of what they want.
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Old 10-13-2020, 04:04 PM   #69
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This thread is so much better when you put idiots on your ignore list.
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Old 10-14-2020, 07:36 AM   #70
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This thread is so much better when you put idiots on your ignore list.
witty comment, good thing you didn't choose to NOT post that
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Old 10-14-2020, 01:27 PM   #71
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I have no idea why we are discussing diseal engines now, but I'm inclined to believe that rtv900 has no idea what he is talking about. Especially from his comment about 100s of things needing to be warn down in an EJ.
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Old 10-14-2020, 01:34 PM   #72
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In a gasoline engine you have either a carburetor or throttle body that acts as a valve to restrict the air flow into the engine. The pistons drawing against this restriction to the air flow is what creates the vacuum. If you open the throttle, the vacuum will go down. At wide open throttle the vacuum level is zero and the intake manifold is at atmospheric pressure.

Diesels don't create a vacuum because they don't have a carburetor/throttle body. It is the Venturi effect that actually creates the vacuum.

That is why a vacuum pump is required for the TH400 transmission and also a hydroboost brake system is required.

You can actually run a diesel without the intake manifold installed.

So both are correct. The diesel eng does not CREATE vacuum, but vacuum is created in deiseal cars by pumps and engineering to have a Venturi effect in places needed.

Last edited by BlackFighter; 10-14-2020 at 02:07 PM.
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Old 10-14-2020, 03:13 PM   #73
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I have no idea why we are discussing diseal engines now, but I'm inclined to believe that rtv900 has no idea what he is talking about. Especially from his comment about 100s of things needing to be warn down in an EJ.
The fact that you don't understand why diesel engines came into the discussion proves you in fact don't understand these topics.
The reasons diesels are applicable are painfully fundamental and basic, which is why several people who are qualified commented on said fundamentals.

The reason you aren't following is because this arena is too advanced for you. You should probably start on sites like "how stuff works" and "basic fundamentals of ICE's for beginners" so you aren't so easily confused.
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Old 10-23-2020, 06:00 AM   #74
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How do I become qualified to post on Nasioc? Also the way I see it if there is pressure in the cylinder and rings are moving up and down, they will seat. Most people who drive cars do not know what a piston ring is. I suppose you could argue about the best possible break in, but aren't you splitting hairs at that point? Any I'm just messing with you rtv I know you really don't think there are 100s of parts I know thats just an exaggeration. For someone to scientifcally prove the best method of break-in on an EJ it will cost more money than its worth. Just drive it how it will be driven.
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Old 10-23-2020, 07:32 AM   #75
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^ok
you said you don't understand why diesels were brought up.
I said it was clearly stated. People keep repeating how vacuum is critical, so I asked how do diesels do this then since they have no vacuum.
Nobody can ever answer that legitimately.
My point was vacuum obviously isn't that critical or it wouldn't work in the other half of all ICE's on the planet.
I thought that was very clear.
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