[tsincaat]

Originally Posted by crabman

Let me just say... I typed that on my phone while waiting for a meeting. I kept trying to cut it shorter to save time but it is hard to explain without going into a little more detail. Lesson learned, don't respond to a thread with what will end up being a long post on your phone, lots of tying errors. O_o

Thanks for that! Very informative. Nice to have someone provide some substantial information on this particular topic.

[IMadeYouReadThis]

Originally Posted by crabman

I'm an engineer. There is no benefit to ring seal that can be attained after the car has left the factory. No directed driving style can either make bad ring seal better or cause you to lose the ring seal you had. It cannot be altered in any way by a buyer through any kind of directed driving style in any way. It's been years since you could even get a diesel engine that could have ring seal issues and that includes the commercial sector where engines are ran on a load cell before leaving the factory. There are a few exceptions to this such as very large engines which even when new are assembled in place and first ran on site. That leaves me the only large area where ring seal is affected by initial startup operation. That is on brand new rebuilds that have not been run. The largest sector in that business is the marine industry where engines are normally "in-framed" in place rather than removed from the vessel. In this case the in frame will not be warrantied unless started up by their own technicians who will run it for about 1 to 2 hours to make sure the load is within their specs to achieve ring seal. If it is not done at that time the engine will be an "oil burner" and nothing can get it back until the next in frame.

None of that applies to this car, ring seal has already been attained at the factory and no of us can do anything to change it by any directed operational parameters of any kind.

While there are other things the two primary break in operation needs are the trans and diff. The brakes also need it but they typically wont be hurt by any kind of operation that includes taking it easy in the first miles. The trans and diff will overheat if too much load is applied before the surfaces have mated. This causes the oil to overheat leading to all the usual lubrication failures that can happen and that heat will make the gears softer with the practical loss out on the road being a weaker gear and more gear whine/noise.

Here is a little cut and paste...

The greatest damage to a new gear set results from running for ten minutes or more during the first 500 miles when the oil is very hot. Any heavy use or overloading while the oil is extremely hot will cause it to break down and allow irreversible damage to the ring & pinion. In order to make them run cooler and quieter, new gears are lapped at the factory. However, they are not lapped under the same pressures that driving creates. The loads generated while driving force any microscopic high spots on the gear teeth back into the surface of the metal. This is called "work hardening". Work hardening is similar to forging in the way that it compresses the metal molecules into a very compact and hard formation. This can only be accomplished if the metal surfaces are lubricated and the gear temperature stays cool enough that the molecular structure does not change. If the temperature of the metal gets hot enough to change the molecular structure, it will soften the surface instead of hardening it. This may seen like a balancing act, but it all happens easily and passively as long as the oil keeps the gear cool while it is breaking in.

End cut and paste...

If you talk to makers of various gears they usually spec heat cycling them, low loads during initial operation, varied load during initial operation, etc. It's been a few years since I did a gear change but I recall Motive having the break in at 3 heat/cooling cycles followed by low load and eventually changing the oil at 500. Those were the good gears (hardened, shot peened, etc) which are a little more fussy than the softer stuff that comes in this car. While various gear/transmission makers spec different break in procedures they all follow something similar and none of them go anywhere close to 1500 miles. The important part is that by 500 miles just like ring seal either the damage is done or it is not. Nothing you can do will change it afterwards either for better or worse.

So why do they spec out to 1500 miles when no directed operation could improve break in further? An easy one. Cars no matter what the mileage on them break less often when they are not being flogged and more often when they are. By going 1500 miles on break in they reduce the total number of warranty claims with a few words. It's a means of cutting costs.

I know this is bringing a thred back from the dead but I just wanted to say thank you for this I was searching trying to make sure I was doing break in properly when I came across this older post I'm thinking 500 miles is where it's at Great post.

[zryan]

I am really bringing this back from the dead. So I've heard of people dyno-ing after the break in period. Some report 375 whp some can get as high as 420 whp. For guys that have numbers closer to 420whp what was your method?

[KyleL]

Originally Posted by zryan

I am really bringing this back from the dead. So I've heard of people dyno-ing after the break in period. Some report 375 whp some can get as high as 420 whp. For guys that have numbers closer to 420whp what was your method?

Using a dyno that reads higher. They can vary significantly.

[dotfiles]

Originally Posted by zryan

I am really bringing this back from the dead. So I've heard of people dyno-ing after the break in period. Some report 375 whp some can get as high as 420 whp. For guys that have numbers closer to 420whp what was your method?

All dynos read differently, especially dynos from different manufacturers. The same car might make 380 on one dyno and 420 on the next. Also people are running different fuel (91, 93, 94) which can count for an additional 10-15hp discrepancy.

[zryan]

Touche, lots of variables at play here.... I guess its dumb to worry about.

[MySS8U]

Originally Posted by Rockhead

Drive it hard, do an oil change at 500 km and don't keep it at a constant rpm for any extended periods of time for the first few thousand kilometres.

don't keep it at any constant RPM, but how long is to long for any constant RPM? 2 minutes, 20 minutes. The manual doesn't specify this either.

[zryan]

Im guessing more like 2 minutes.

[MySS8U]

I guess 2 minutes does make more since. The manual also says the camaro will use more oil and gas during the break in period. So if you was constantly revving between gears randomly (4rpm and below) it would burn more oil and gas.

[Boosted_ST]

Originally Posted by MySS8U

don't keep it at any constant RPM, but how long is to long for any constant RPM? 2 minutes, 20 minutes. The manual doesn't specify this either.

Extended, to me, means anything more than at least 15 minutes.

Seems like the best break-in procedure is to keep it at under 4K RPM for 500 miles, then do an oil change.

Drive it normally for additional 1,000 miles (1,500 total miles now on the ODO) then do another oil change with differential fluid change.

Key is to not go hard on the vehicle until it is fully warmed up.

[Tha_Infamous_E]

The warming up process is a old tale, you don't need to do it for newer cars nowadays, especially performance cars like these. Regardless, it's good to take it easy the first thousand or two miles ANYWAYS, learn about your car, how the body moves, etcetera before hammering it on every turn. By the time you understand your car, it'll take a good thousand or two miles anyways.