[Dysan911]

I've realllly reallly tried to stick to the break in procedure. I typically keep in under 4k RPM and I vary my speed and don't exceed 80mph. However on a rare occasion I've held a gear to 4k RPM and punched it just for a sec or two and got out of it before redline. I've might have done this maybe 3 times. I'm still just over 800 miles on my engine.

I've heard both schools of thought when it comes to breaking in the motor but never really knew which way to go so hopefully I didn't just go and ruin things for those couple moments of weakeness.

[Ryephile]

Originally Posted by hotlap

How does breaking in the engine in a less than optimal way "keep the OEM out of court".

Any sort of specific advice they offer will hold them liable. Imagine if the owners manual said "hold WOT until redline". You'd have people crashing left and right and then suing the OEM. So any wording like that, regardless if it's good advice, will never come to light. It's the same reason why you see plastered in all car commercials "professional driver on a closed course".

Originally Posted by Donner

Hello, ....
Bottom line: If a better service life and greater performance matters to you, follow the break in advice given by the engineers.

Kindest,

Donner

Therein lies the crux of the issue. What ends up in the owners manual is in no way the words of the engineers.


So, some guy makes a video where he reads a few owners manuals and makes a proclamation does not equal wise or experienced advice. The closest thing he said to good was when he talked about engines that are already broken in, and to just drive it.

[nbryant]

Originally Posted by Ryephile

Not really. The manual is going to be phrased to keep the OEM out of court. Optimum break-in for the average owner is a very distant 2nd.

Damn, didn't know we had an all knowing expert in our midst!

[pdiddy972]

Originally Posted by Ryephile

There are theories based on logical fallacies, and then there are scientific conclusions based on soundly collected data. The video trumpets the prior. You getting emotional about it shows you prefer dogma over data.



This kind of anecdotal evidence is part of the problem. Unless you've done several break-in styles and then did measurements on which was most effective, your engine running well could've just as well been a result of dumb luck.


...and born-to-fish trying to use my current DD as some sort of evidence that I'm wrong is quite amusing. I challenge all of you to try out your thinking cap instead of grabbing pitchforks.

Have you seen the MotoTune Guy's website? He's done MANY breakins and broke down the engine to see the pistons and rings so it's not anecdotal or wishful thinking. Breaking in hard is the way to get the rings seated during the short window while that's still possible.

[pdiddy972]

Originally Posted by hotlap

Wouldn't it be fair to assume the manufactures have test several break-in styles and then did measurements? Result being the break-in procedure published in the manual.

It's equally likely that bean counters know that more cars will make it past the warranty period with a gentle breakin. Assuming their goals of saving on warranty expenses align with your goals of maximum HP and not burning oil is overly optimistic.

[vtirocz]

Originally Posted by Ryephile

There are theories based on logical fallacies, and then there are scientific conclusions based on soundly collected data. The video trumpets the prior. You getting emotional about it shows you prefer dogma over data.



This kind of anecdotal evidence is part of the problem. Unless you've done several break-in styles and then did measurements on which was most effective, your engine running well could've just as well been a result of dumb luck.


...and born-to-fish trying to use my current DD as some sort of evidence that I'm wrong is quite amusing. I challenge all of you to try out your thinking cap instead of grabbing pitchforks.

Can you please provide evidence to support your claim? What criteria are you using to gauge better or worse?

[DGthe3]

Originally Posted by Ryephile

Any sort of specific advice they offer will hold them liable. Imagine if the owners manual said "hold WOT until redline". You'd have people crashing left and right and then suing the OEM. So any wording like that, regardless if it's good advice, will never come to light. It's the same reason why you see plastered in all car commercials "professional driver on a closed course".

If the manual exists as a legal protector, why do they recommend against hard stops? If 'well, the manual said ... ' is a valid argument, anyone with a new car could blame the manufacturer every time they run a red light or a stop sign or rear end someone or hit a tree or whatever. And yet, thats not a thing.

Similar thing goes for hard cornering. 'Sorry your Honour, I couldn't swerve to avoid them because the owners manual said not to make any hard turns during the first 200 miles.'

[Ryephile]

Originally Posted by pdiddy972

Have you seen the MotoTune Guy's website? He's done MANY breakins and broke down the engine to see the pistons and rings so it's not anecdotal or wishful thinking. Breaking in hard is the way to get the rings seated during the short window while that's still possible.

Definitely.

[Ryephile]

Originally Posted by DGthe3

If the manual exists as a legal protector, why do they recommend against hard stops? If 'well, the manual said ... ' is a valid argument, anyone with a new car could blame the manufacturer every time they run a red light or a stop sign or rear end someone or hit a tree or whatever. And yet, thats not a thing.

Similar thing goes for hard cornering. 'Sorry your Honour, I couldn't swerve to avoid them because the owners manual said not to make any hard turns during the first 200 miles.'

You're deviating into brake pad bedding. At that point we might as well throw tire scuffing, clutch bed-in, wheel bearing seating, and gear mesh break-in into the mix. On a car that's fresh off the production line, they all need some kind of break-in period.

Of course, your paraphrasing of the owners manual missed the important part of the sentence in the disclaimer that indemnifies the OEM: "...except emergencies...". I'm not sure why some people here are trying so hard to misunderstand the physics of the situation just to defend a vlogger trying to earn your YouTube click.

[zapatista]

Originally Posted by Ryephile

You're deviating into brake pad bedding. At that point we might as well throw tire scuffing, clutch bed-in, wheel bearing seating, and gear mesh break-in into the mix. On a car that's fresh off the production line, they all need some kind of break-in period.

Of course, your paraphrasing of the owners manual missed the important part of the sentence in the disclaimer that indemnifies the OEM: "...except emergencies...". I'm not sure why some people here are trying so hard to misunderstand the physics of the situation just to defend a vlogger trying to earn your YouTube click.

Ok, ok...I was gonna buy a Camaro but you've convinced me to get a turbo'd NA 1.6l. This is what your really trying to say? Cuz all the rest of your answer makes no f***ing sense.

[AndyUK]

Originally Posted by nbryant

Really?

Owners manual, page 207, first of 5 recommendations:

"Avoid full throttle starts and abrupt stops."


Not sure what you were reading.

You are isolating an single statement and implying it means something that it doesn't. If you read all of the material available from GM on break in procedure it fills in the blanks.

There's a break in manual specifically for the LT1 engine.
It does not contradict that text from the camaro manual.

You will note that the camaro manual says avoid full throttle starts and abrupt stops, it does not say to avoid full throttle at all times.

It seems some people can't understand plain English. They assume "avoid full throttle starts" means "baby the throttle", but it doesn't.

The engine needs load to bed in correctly, the LT1 engine break in manual is very explicit in requiring part and full throttle runs (up to 4000rpm and with in gear rundown) as being the correct procedure.

If you drive the whole of the first 1500 miles with less than 50% throttle then you'll end up with a motor thats not sealed as good as it could be and down on power.
Given the hundreds of dollars people seem to be willing to spend to gain 5 to 10hp, taking the 5 minutes to find and read the engine break in manual doesnt seem too difficult.

Credit to Matt for posting these, please note that these do NOT contradict the chevrolet camaro manual instructions, they are just more detailed. The youtuber in the video has made the same mistake and assumed the wrong thing about what the Corvette/Camaro instructions actually mean.;

Originally Posted by MattDinOC

I went with a sort of hybrid approach when I got my SS. I didn't like the vague instructions that Chevy includes in the owner's manual, but seeing as how I'm planning to keep this car for a very long time, I also am not going to go out and thrash it just because someone on the internet said that's the right way to do it. Someone here once posted an image of the break-in instructions that Chevy provides with its crate engines. So I went and found the instructions for our engine and followed those guidelines. Here's the PDF of the full instruction book.

The break-in instructions that are relevant to us as buyers of a new LT1-powered Camaro:

7. The engine should be driven at varying loads and conditions for the first 30 miles or one hour without wide open throttle (WOT) or sustained high RPM accelerations.
8. Run five or six medium throttle (50%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
9. Run two or three hard throttle (WOT 100%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
10. Change the oil and filter. Replace the oil per the specification in step 1, and replace the filter with a new PF64 AC Delco oil filter. Inspect the oil and the oil filter for any foreign particles to ensure that the engine is functioning properly.
11. Drive the next 500 miles (12 to 15 engine hours) under normal conditions. Do not run the engine at its maximum rated engine speed. Also, do not expose the engine to extended periods of high load.
12. Change the oil and filter. Again, inspect the oil and oil filter for any foreign particles to ensure that the engine is functioning properly.

I skipped the oil-and-filter change in step 10, but did the one in step 12. I was at 700 miles when I did that one. Next oil change will be a the normal interval.

To break in the rest of the drivetrain properly, I am avoiding redlining and smoky burnouts until after I hit 1500 miles. Running it hard from time to time, not babying it, but also not ignoring the instructions in the vehicle owners manual.

Matt

[AndyUK]

Originally Posted by DGthe3

If the manual exists as a legal protector, why do they recommend against hard stops? If 'well, the manual said ... ' is a valid argument, anyone with a new car could blame the manufacturer every time they run a red light or a stop sign or rear end someone or hit a tree or whatever. And yet, thats not a thing.

Similar thing goes for hard cornering. 'Sorry your Honour, I couldn't swerve to avoid them because the owners manual said not to make any hard turns during the first 200 miles.'

A manufacturer isnt going to get sued just because someone driving did something stupid and it just happened to be in one of their cars. Where liability creeps in is if say the rear diff locks up and forces you off the road or careening through the front of a coffee shop. The liability statements are there to help protect where there is a potential fault with the car, not just for general dangerous driving.

[Corner carver]

Originally Posted by Ryephile

There are theories based on logical fallacies, and then there are scientific conclusions based on soundly collected data. The video trumpets the prior. You getting emotional about it shows you prefer dogma over data.



This kind of anecdotal evidence is part of the problem. Unless you've done several break-in styles and then did measurements on which was most effective, your engine running well could've just as well been a result of dumb luck.


...and born-to-fish trying to use my current DD as some sort of evidence that I'm wrong is quite amusing. I challenge all of you to try out your thinking cap instead of grabbing pitchforks.

3rd engine I've broke in THIS year this way... All run fantastic

[Corner carver]

Originally Posted by Donner

Hello, I posted the following statement in another thread about "Who's doing a hard break in?" That one, like this was addressing a similar issue. There are plenty of folks that have their own minds made up and for you, have at it. To anyone that actually is concerned about whether the manufacture is correct, here's my take.

Hello,

If I might offer some insight into breaking in the motor. There is the school of thrash it and trash it and I subscribe to that belief. The issue with rushing the breaking in of the motor components is that no seat of the pants measurement will be able to show one what was lost by not doing right by the engine and the advice of the engineering professionals that designed the motor.

To spare the readers a long discourse, consider just the piston and rings. The cylinder that the pistons ride inside of are nearly circular cylinders but they are made by tools that leave a slightly abrasive uneven surface and cutting marks through a process known as honing.

The rings sliding up and down within the cylinder’s walls will eventually polish these minor ridges away and create an optimal interface if properly broken in, or something less than that if the process is rushed or the motor is abused prematurely. The pistons themselves contain ringlands (grooves that are machined or cast to create circular trenches) but they are not circular. That is because the piston isn’t exactly a circle either. Its proper shape, when cold, is elliptical when viewed from above (looking down) and conical when viewed from the side. The top of the pistons are truncated cones replete with whatever shaping that the valve relief was designed to create.

The reason that the pistons are not full circles when cold is because of expansion. Metals grow in proportion to temperature in an “inches per inch” relation. There is more metal (solid in fact) at the top of the piston (the dome) and a complete hole at the bottom extending upwards. Since the top is solid, it grows more in relative diameter than does the bottom of the skirt but once up to temperature, it will become a circular cylinder as well.

Now consider that the wrist pin has protrusions on the internal walls of the piston’s insides. The piston will be narrower by the holes of the wrist pin and wider along the transverse axis. Because of the extra metal needed to support the wrist pins, the piston will expand further in that direction and again, become circular once it is heated up. Why this matters is that the rings are not fully supported in the ringland until the engine is at operational temperature.

As the pistons cycle up and down, the flexibility of the rings cause them to wave in relation. Rings do not remain flat because until the motor is broken in they are being jolted about by the honing marks. Since they do wave, the tips at the upper and bottom edges of the rings can get chipped or gouged if the engine is pushed too hard before the full sealing and polishing has occurred.

What this will mean in the long run, is that the rings will not hold the most pressure possible thus the engine loses compression (admittedly it’s a very slight difference at first and will degrade more rapidly than a properly broken in motor would over time). Those chips create little wedges that can allow more pressure to bypass the interface so maximum compression suffers.

Why altering the range of RPM and the load is important is because those wavering rings get the best chance to polish the surface rather than wear in ruts. It’s better for the rings and the cylinder walls to limit the power early on.

Bottom line: If a better service life and greater performance matters to you, follow the break in advice given by the engineers.

Kindest,

Donner

Great write up, thank you!