my thoughts about break in

[CircuitJerk]

Originally Posted by choi0706

I kept mine @ low revs, and got a CEL in 300 miles.. it never went away.. Even with swapped cam sprockets, ecu replacements, etc.. I will not be doing this on my replacement car..

I believe your misfortune is not a result of your break in technique.
Not telling you to do the same thing over, but that experience should have no bearing on it. At least that's my opinion..

[choi0706]

I've also found driving more aggressive made the light go away temporarily..

There is some credible source on the fb page that the cel came on mostly lightly driven/broken in vehicles..

[McDeLtA_T]

Originally Posted by Dezoris

At 14 miles, let it warm up. Took it on an open road and slowly worked up the engine speed in 3rd gear all the way to redline and let it slowly drop down. Wash rinse and repeat. All over the rev range varying loads. for the first 500 miles then dumped the oil.

I never understood why you need to break in a motor for 1000 miles by keeping RPM down? Maybe they go under the assumption people are not going to change that oil for 5000-7000 miles?

You must keep the rpm low for your break in period; as RPM or radial velocity increases (w), your acceleration (a) is increased as a square. a=w^2*r. Remember from physics, F=m*a? The higher the rpm, the higher your con rod's and pistons have to accelerate to get from TDC to BDC. This in turn creates excessive force on your crankshaft bearings. This force slams the unworn-in bearings and creates terrible form-ability between the crank journal and bearing. Your bearings need to form to the journals uneven surface to properly allow a thin film of lubrication to separate the two surfaces.

It is imperative that you wear in your bearings properly first or else you can cause a majority of problems. This also goes for the rest of your engine. This is why they specify you to maintain an rpm below a set value in the operating manual. See this link below for info on bearing wear problems, I hope this scares anyone from neglecting the advice of the manual...Your car may run fine for the first 30k but it can lead to a host of problems in the long run if you don't "wear-in" your car properly.

http://www.bobistheoilguy.com/bearin...aranalysis.htm

[Dezoris]

Originally Posted by McDeLtA_T

You must keep the rpm low for your break in period; as RPM or radial velocity increases (w), your acceleration (a) is increased as a square. a=w^2*r. Remember from physics, F=m*a? The higher the rpm, the higher your con rod's and pistons have to accelerate to get from TDC to BDC. This in turn creates excessive force on your crankshaft bearings. This force slams the unworn-in bearings and creates terrible form-ability between the crank journal and bearing. Your bearings need to form to the journals uneven surface to properly allow a thin film of lubrication to separate the two surfaces.

It is imperative that you wear in your bearings properly first or else you can cause a majority of problems. This also goes for the rest of your engine. This is why they specify you to maintain an rpm below a set value in the operating manual. See this link below for info on bearing wear problems, I hope this scares anyone from neglecting the advice of the manual...Your car may run fine for the first 30k but it can lead to a host of problems in the long run if you don't "wear-in" your car properly.

http://www.bobistheoilguy.com/bearin...aranalysis.htm

With the oem fill and massive amounts of moly I don't see how the engine is not already worn on from the factory or the first 20 miles?

My UOA at 500 miles was no different than any others posted and no signs of crank wear.
I understand the physics it just does not take 1000 miles of low rpm to wear in these parts.

[McDeLtA_T]

Originally Posted by Dezoris

With the oem fill and massive amounts of moly I don't see how the engine is not already worn on from the factory or the first 20 miles?

My UOA at 500 miles was no different than any others posted and no signs of crank wear.
I understand the physics it just does not take 1000 miles of low rpm to wear in these parts.

Your right, in most cases it doesn't but engineers like to do safety factors of 2 lol

[brillo]

The bearing comment is interesting and the first plausible reason I've read for a light breakin procedure. Not sure the bearings need a 1,000 miles but its a interesting data point

[qijian]

For me, i'm too paranoid to take it over 4k if its not necessary... but sometimes I find myself shifting at 4.5k but that's probably as high as i'll take it until i hit 1k miles.

[EBMCS03]

Originally Posted by FR-S Matt

It absolutely killed my gas mileage on the trip to SA. I've noticed anything above 75-80 tanks your MPG. Anything below, I've been getting 27-28.

69-73 has been the best mpg for me. Haha

[Wankel Rex]

Dealer told me 500 miles under 4,000 rpm. At 501 I let loose and have been for the next 11,000 miles. Most weekends I'm searching for back roads on which I can open it up legally while pushing the car.

[FR-S Matt]

I think my gas mileage might go down a tad a result of my cold air install. I'll keep an eye on it between tanks. I've had a heavy foot since I got it installed this round so this one doesn't count!

Best I've gotten so far is 30.2 on a tank.

[bdohazelnuts]

I plan to do a bit of a dual break-in. I am going to spend all tonight breaking it in pretty hard. Let it warm up to operating temp, run it up through the gears slowly to open throttle and change just before redline, park it until completely cool (an hour or so), repeat about 10 times or so...

Then (try to) keep it under 4k until I hit 100 miles (then change the oil and put in some 5w30 - probably royal purple, as it worked great in my 'tard turbo Miata), 4500 to 200 miles, 5000 to 300 miles, 5500 to 350 miles, 6000 to 400, 6500 to 500, and after that call it good.

[boead]

Originally Posted by SkullWorks

my engine saw redline in the first 100 miles...all my engines (most of which I build personally) see redline either during breakin on the dyno, or in the first 100 street miles, an understanding of metalurgy and the surface finishes in the bore will tell you why this is not only OK but preferable.

Break in is the period of time where the motor "seats" the rings to the cylinder walls, repetitive friction on a surface "work hardens" the material, what you ideally want is the rings to use the minimal abrasive action from the cylinder finish hone to normalize the ring shape to the individual cylinder wall, this requires cylinder pressure to force the rings against the cylinder wall, WOT and high rev's create cylinder pressure. and are therefore REQUIRED to create the best ring seal possible, before you work harden the cylinder walls and the ring faces. (which are already appreciably hard)

There once was a time before what is known as plateau honing, that you could wear out the hatching left in the cylinder with too much cylinder pressure during break in, but those days have long since past.


So why is there a break in procedure then (because i know you all think im stupid by now...obviously) well because the Manufacturer knows that you will still get an acceptable ring seal driving gingerly, worst case scenario you lose some cylinder pressure and a few HP, maybe burn a bit more oil consumption (with a mfg specified 1000 mile break n procedure) but the manufacturer has a lower chance (albeit slight) of brand new car engine failures. Also the clutch really does need about 300-400 miles of nice easy engagement without significant shock to ensure optimal life.

Take with a grain of salt, but remember always that corporations rarely have you or your property's best interest in mind, when they write literature, it is to cover their ass...not protect your investment.

I just past 1000 miles, the last 600 was a round trip drive from Long Island (NY) to the Catskills.
Ive been taking it easy but shes seen a little redline BUT Ive been keeping it to 6000 more for the rest of the cars sake.
As this posted said, its more about the clutch and other parts.

I was surprised how quickly she got to 110mph, plenty of pep up there too!
I think the Audi A4 turbo was surprised too or maybe he had no balls.

She a bit of a nasty bitch this one. My RSX is polite and somewhat reserved.

[SkullWorks]

Originally Posted by McDeLtA_T

You must keep the rpm low for your break in period; as RPM or radial velocity increases (w), your acceleration (a) is increased as a square. a=w^2*r. Remember from physics, F=m*a? The higher the rpm, the higher your con rod's and pistons have to accelerate to get from TDC to BDC. This in turn creates excessive force on your crankshaft bearings. This force slams the unworn-in bearings and creates terrible form-ability between the crank journal and bearing. Your bearings need to form to the journals uneven surface to properly allow a thin film of lubrication to separate the two surfaces.

It is imperative that you wear in your bearings properly first or else you can cause a majority of problems. This also goes for the rest of your engine. This is why they specify you to maintain an rpm below a set value in the operating manual. See this link below for info on bearing wear problems, I hope this scares anyone from neglecting the advice of the manual...Your car may run fine for the first 30k but it can lead to a host of problems in the long run if you don't "wear-in" your car properly.

http://www.bobistheoilguy.com/bearin...aranalysis.htm

Please refrain from using ignorant scare tactics to misinform people, I'm not sure what you have to gain by peddling bad info but no where on that chart of common bearing issues did it mention anything to back up your misguided statements about wearing in bearing...

Do what you will with your own car but don't try to explain things you don't understand, coming in here talking about physics, with no understanding of the subject at hand makes you look credible to people looking for actual information but to anyone who knows how a bearing works you look like a fool.



To clarify the mess you laid out for everyone, If a bearing touches your crankshaft it doesn't "wear-in" it wears OUT, bearings should only ever touch the journal (rod or crank) when the engine is off. that's the ENTIRE POINT OF FORCED OILING. The oil floats the crankshaft and rods on a thin layer of oil under pressure, its called a Hydrodynamic bearing.

This idea you seemed to develop that a bearing needs to form to the uneven surface of a Journal tells me you have no experience whatsoever in engine assembly or precision...anything. The crankshaft has hardened and ground surfaces for all journals, aswell as the seals on both ends. your average OOR (out or Round) condition on these surfaces will be less than .00005" that's "fifty millionths" of an inch, there is no "wearing in" of bearings, there is no "uneven" surfaces



It's posts like this full of misinformation that give forums and the internet in general the reputation of being full of know it all's who know nothing.

[chenshuo]

On the subject of break-in, i'd trust the people who actually built the car than some people who thinks they know how to break-in. It's not just the engine, but the entire car that you're breaking-in.

There are people that even say "oh the manual is written by lawyers." People who say that are ignorants. I worked in a company that did technical writing. Manuals are written by COPY WRITERS, not lawyers. Each copy writer is paired with a subject expert. That's how manuals are written.

For those that say "the manual is just written by lawyers so i'm not gonna follow the manual", it's your car, do whatever you want with it.