engine break in
Racer
Joined: Aug 2008
Posts: 449
Likes: 0
From: Morganton NC
Race Director
Joined: Jun 2005
Posts: 10,909
Likes: 2,701
From: Phila Suburbs 2023 C8 & 2013 650ix
No matter how finely machined they are, any rubbing mechanical components, even well lubricated ones, experience a break-in or run-in period when the two components "learn" to conform to one another under the influence of heat, mechanical and hydraulic distortions and pressure gradients. Surfaces that are too smooth become rougher, those that are too rough become smoother. Geometry also changes in subtle ways in terms of roundness, flatness, concentricity, squareness, and so on.
If completed under reasonably controlled conditions, that is without excessive loads, velocities and temperatures, this natural process "hones' the rubbing surfaces, increasing the total "real" rather than "apparent" load bearing surfaces, improving conformance, optimizing clearances and improving hydrodynamic lubrication between the rubbing surfaces.
"Rushing" the process, such as through excessive loads and velocities, leads to galling, seizing, and microscopic welding of opposing surfaces which bear against one another, shortening the operating life of the mechanism, be it an engine, alternater, water pump, transmission, differential wheel bearings, etc., etc.. The choice of conforming to recommended break-in procedures is yours.
If completed under reasonably controlled conditions, that is without excessive loads, velocities and temperatures, this natural process "hones' the rubbing surfaces, increasing the total "real" rather than "apparent" load bearing surfaces, improving conformance, optimizing clearances and improving hydrodynamic lubrication between the rubbing surfaces.
"Rushing" the process, such as through excessive loads and velocities, leads to galling, seizing, and microscopic welding of opposing surfaces which bear against one another, shortening the operating life of the mechanism, be it an engine, alternater, water pump, transmission, differential wheel bearings, etc., etc.. The choice of conforming to recommended break-in procedures is yours.
Spoken like a true mechanical engineer that has been educated in the science of tribology which is the science of the mechanisms of friction, lubrication, and wear of interacting surfaces that are in relative motion.
When someone says "drive it like you stole it from the first mile" think about what the proven scientific facts are.
Team Owner
Joined: Sep 2000
Posts: 25,009
Likes: 2,707
From: Far NW 'burbs of Chicago
St. Jude Donor '13
page 2-22
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For the first 1,500 miles/2414 km:
Do not participate in track events, sport driving schools, or similar activities during the first 1,500 miles/2414 km.
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Le Mans Master
Joined: Sep 2006
Posts: 5,606
Likes: 88
From: Sammamish WA
Why not take it easy for the first 500 miles...it couldn't hurt....
For some on here, 500 miles will take three months, but you could just actually drive it for a week and then banish it to the garage to wash and wax it for the rest of its life...
Seriously though...its only 500 miles...why not go easy on it?
And just because some people do dumb things and then don't have any problems...that really shouldn't be an endorsement of doing dumb things. Ask Wolfdogs about the tire plugs...just because some people have plugged their 186mph rated tires, and then have not had problems....this is not going to get me to plug my 186mph rated tire when the entire industry says it shouldn't be done. Sheesh....
For some on here, 500 miles will take three months, but you could just actually drive it for a week and then banish it to the garage to wash and wax it for the rest of its life...
Seriously though...its only 500 miles...why not go easy on it?
And just because some people do dumb things and then don't have any problems...that really shouldn't be an endorsement of doing dumb things. Ask Wolfdogs about the tire plugs...just because some people have plugged their 186mph rated tires, and then have not had problems....this is not going to get me to plug my 186mph rated tire when the entire industry says it shouldn't be done. Sheesh....
This is one of the best responses I've seen for a long time on the forum. I figure the manufacturer knows best, or at least I'll give them the benefit of the doubt when forking over $50 large for a new car.If there wasn't some value in observing the break in period as suggested by the Manuf, Then why do they bother to tell you to do it in the first place.
Besides, if I'm not mistaken, All the C6s have some sort of "black box" that can tell the service depratment your maximum RPMS and Speed etc when you take it in for service. I may be wrong, but I'd sure be a bit red-faced taking my new C6 back to the dealer the week after I bought it asking for warranty work on a broken engine that I'd just ran beyond the rev limiter for 10 miles in second gear.
The gear "break in" as suggested in other posts makes a lot of sense to me as well.
Come to think of it, I don't think my '07 has ever been driven beyond the suggested break in limits since I took delivery. Hey, I'm retired. I'm not in any hurry...
Racer
Joined: Feb 2008
Posts: 485
Likes: 1
From: Texas
Hmmm... Interesting change for 09. I could not find this in the 08 manual. I did the 500 mile break-in, but at 501 all bets were off!
