http://www.mototuneusa.com/break_in_secrets.htm

I've heard people say this before. So how are you breaking your motor in, Dave :) It really gives you something to think about, doesn't it?

wow. VERY interesting indeed...i'm gonna have to get some more views on this, hehe

hhhhhmmmmmm........................

Well I have been taking it easy on mine. I have almost 300 miles and I havent boosted much except once today. I hit 8 psi today..hehe... But the real reasone I am not boosting yet is that my mechanic only torqued my ARP nuts to 53 lbs which is the stock torque spec and they call for 85-90lbs. So next week I am going to get the nuts re torqued and then run 10-12 psi for now untill the ignition.

Nothing new, there are about 100 ways that people break-in engines. Some use no coolant and others believe that the break is good enough once you pass your cam break-in period. It's up to you and what you feel comfortable, but the one thing I absolutely agree with is the fact of letting your motor get to op. temp. Just think, NASCAR builders don't have all day to let a race motor break-in before every race. ARP bolts and studs have to be stretched, that's why they have higher TQ specs. Make sure that your builder uses the little bolt stretch gage that it comes with.

damn, I want a new motor to break in, guess I'll have to spray a 150 shot :)

I think that "motoman" is right. I took it really easy on my car with the first engine, and when I pulled my pisotns they looked like ass. Engine #2 I started it, warmed it up good(about 15 min) then reved between 2-5k for about 5 min, shut down, looked for oil leaks...ect...ect, then drove it on a deserted highway, in second gear gunning it every so often. But not reving it past 6k. When I pulled the pistons on that one, they were near new looking, like when I put them back in! nice and shiny still. Go figure.

i'm sorry to reply to an older posting like this but i just read what motoman said, and i personally don't think i've read more horse crap in my life.

the pressures of combustion are equal and consistent no matter what aspect of the combustion chamber you are looking at, (tops of pistons, sides of pistons, tops of rings, sides of rings). we all know the seal doesn't occur because of 5 lbs of tension against the cylinder walls, but thats why pistons have rings lands, the rings sit in them!!! otherwise how would the piston move??...not to mention, if his point of the gases behind the ring make the seal, how do total seal pistons work?....hmmmm. i understand that all those pressures are exerted downward on the piston, and the gases do make a strong seal, but there's more to it than just that.

and motoman says the only purpose of the tension of the rings is to scrap oil?...correct me if i'm wrong, but isn't that the purpose of the oil control ring?...oil shouldn't, and doesn't, make it to the top ring ever, assuming your bore is in spec.

"The rough crosshatch pattern in the cylinder bore acts like a file "...wtf!! do u guys have any idea how hard the rings are?..those little left over crosshatches don;t file your rings down to fit properly...this guy is rediculous.

sorry guys maybe i'm all wrong, but i'd hate to see some kid who just spent big bucks on his motor read this and go beat the piss out of his brand new motor and ruin it...thats mainly why i wanted to reply, go with what works. how many ppl on here started up their new motor and ran it wide open...otherwise how many ppl let their car warm up properly and drove their car calm to properly let it break it. well i did the later and i have 15000 since my rebuild and my compression is fine and i've never run better.

just wanted to say that, sorry for the big venting but without any evidence to back that bunch of crap up, i'd feel bad if i didn't say something...lata guys.

well when satan replaced my short block I did some research to find the best way to break in an engine and I found from multiple sources that the best way is to take it easy on the engine for the most part, but that it is also good to accelerate rapidly and follow that with rapid deceleration. They said that it helps the rings seat better. I also found that the engine should not be kept at a constant rpm for too long and when taking long trips on the highway you should vary the rpm by switching gears every minute or so. Obviously this way worked, becuase I am now experiencing ZERO blowby where with the previous block it got to the point where I couldnt make it 3000 miles without adding oil

>
>the pressures of combustion are equal and consistent no
>matter what aspect of the combustion chamber you are looking
>at, (tops of pistons, sides of pistons, tops of rings, sides
>of rings). we all know the seal doesn't occur because of 5
>lbs of tension against the cylinder walls, but thats why
>pistons have rings lands, the rings sit in them!!! otherwise
>how would the piston move??...not to mention, if his point
>of the gases behind the ring make the seal, how do total
>seal pistons work?....hmmmm. i understand that all those
>pressures are exerted downward on the piston, and the gases
>do make a strong seal, but there's more to it than just
>that.
>

Actually, the seal in the chamber comes from the seal at the ring-to-cylinder wall, AND the ring-to-ringland. Pressure does indeed pushout the rings, it has to, or else it wouldnt seal.


>and motoman says the only purpose of the tension of the
>rings is to scrap oil?...correct me if i'm wrong, but isn't
>that the purpose of the oil control ring?...oil shouldn't,
>and doesn't, make it to the top ring ever, assuming your
>bore is in spec.


From what i understand, the oil controll ring is just that. It "controlls oil flow, not just for scraping. It sets how much oil is getting onto and off of the cylinder walls. The second piston ring is actually the oil scraper ring, oil should not get above this ring. The top piston ring is the compression ring, where almost all of the compression sealing takes place.


>"The rough crosshatch pattern in the cylinder bore acts like
>a file "...wtf!! do u guys have any idea how hard the rings
>are?..those little left over crosshatches don;t file your
>rings down to fit properly...this guy is rediculous.

Well, yes and no. The main purpose of the crosshatch, is to help the rings seat to the cylinder. Something needs to wear slightly. The hardness of the rings is what "polishes" the cylinder very slightly, seating the cylinder to the rings. A proper crosshatch is also needed to help oil distribution on the cylinder walls.

>sorry guys maybe i'm all wrong, but i'd hate to see some kid
>who just spent big bucks on his motor read this and go beat
>the piss out of his brand new motor and ruin it...thats
>mainly why i wanted to reply, go with what works. how many
>ppl on here started up their new motor and ran it wide
>open...otherwise how many ppl let their car warm up properly
>and drove their car calm to properly let it break it. well
>i did the later and i have 15000 since my rebuild and my
>compression is fine and i've never run better.

I think the rings will seat with the cylinder wall either way really. If it doesnt happen right away from a full throttle run, then i really dont see how it cant while just camly driving it around.


>just wanted to say that, sorry for the big venting but
>without any evidence to back that bunch of crap up, i'd feel
>bad if i didn't say something...lata guys.

Thanks :) I really want to look into this though. The motoman makes some good points and theories, we just need to back them up with more info IMO. Engine builders are stubborn though, and set in their ways, so its really hard to find the truth. Also, i just cant see either how being "hard" on a new motor is bad. Worst case is you get more blowby until the rings actually seat...

A guy I know used to build Nascar cars and motors. Currently he's dropping a chevy 4.3L into a Mazada RX-4. the guy knows his shit. in any case.. he said to run the new motor like how you plan to run it in the future. if you are gonna race it and run it hard, then do that from the get go. and after that he said "if something breaks, then it wasn't built right".

just thought i'd through that in there.

man, i plain on rebuilding soon and boy am i ever confused now both ways make sence to me?

Breezio is pretty right on with the guy you spoke to. If it's going to break, it will anyway. The reason for such a variation of speed and rpms mostly follows an old-school way of making sure your cam doesn't get a flat spot that will coax the motor into having almost a "flat" spot in the powerband. It's not really true b/c now crane cams (as well as many others) tell you to break in the cam by keeping the motor running for about 15-30 mins. at the same rpm and then drive the car while steadily increasing and decreasing speeds and rpms. New Vettes in thier manuals and owners videos say to vary speed and rpms until 500 miles then you can let her rip. Keep in mind that this is an all alluminum motor. I would say no matter how hard you run it, your craftmanship should prove it's self. Just as the motoman said, the motor must be within operating temps before really getting on it. Nobody has mentioned bearings in this conversation which is usually what goes in a regular, well tuned motor. I would make sure that the rotating assembly is completely inline and have a reliable dial-indicator to check this. That is a good killer other than oil starvation for bearings. If you want to run the hell out of the motor, then do it. If you don't, then don't. It depends how you will drive it. Oh; BTW, cross-hatches on cylinder walls DO shape how rings wear. Otherwise, what would be the point of "breaking the glaze" when you rehone cylinder walls for new rings.

man now I'm confused. I don't race my car all the time so I guess I'll take the "take it easy" route.

well i do agree with the points u guys are makin...but as far as the crosshatches go, yeah they have a small part in shaping the rings, like maybe putting a slight polish on them, but what motoman says that i don;t agree with is that it acts as a file...and if u don;t run it hard for the first 20 min of motor use, you have to pull the pistons back out, buy new rings and re-hone...oh c'mon..lol.

Keep in mind that there are different kinds of rings available too. I used to use chrome-moly rings in 454's that were going to be ran hard(racing). They require that a ball-hone NOT be used b/c it has silicon in it and that would cause lack of seal, so you would get excessive amounts of oil blow-by and consumption. Though the only bike motor I ever built was dirtbike single, the rings for them I'd almost promise have different qualities just because they run at higher rpms for longer periods. If you are confused and building your own engine, then do what you feel comfortable with. If the specs that you followed were to the "T" then go ahead and run it. I think there's a misconseption of what motoman had said. He's saying run it hard ONLY after the parts are nice and warmed up. He's not saying to get it fired up and smoke tires leaving the driveway. I don't really agree with how one-sided his page is and the fact that he's not here to hear the questions that are being asked. An engine is your baby but it is also a cluster-f*ck of parts and pieces that really don't have feelings towards you. My outlook is that, if you want to run it hard, go for it. Will it hurt anything, probably not. Be consistent and have common sense. I watch many funny cars that literally have the engines built, fired, tuned, and then run a 7/8 second pass. If you see blow-by being a problem, run it a tad harder. Heat does wonders for breaking in rings and bearings.