Join Date: Jun 2008
Location: North Carolina
Bullitt Year: 08
Bullitt Color: HG
Bullitt Serialized Number: 0852
First, this is my opinion only. Based upon no facts whatsoever.
I think the magic time is following the first oil change. When an engine is first assembled, there is "break in" oil in the engine. Note, it is not really a different oil, as such, but high quality oil and when first started, it will wash the assembly lube off the parts and that creates 'break-in" oil. The "assembly lube" actually contains some abrasive agents that will allow the bearing, rings, cams, etc to wear enough to allow the surfaces it mate. It is during this period that I would take it easy to allow the parts to "mate" to each other.
Once you do your first oil change, that is when the "super" slick non-friction oil starts being used. At this point all surfaces will be mated and very little (if any) wear should be expected from that point forward. So conserve driving at that point will have little, if any, impact of the engine. If step one (break-in) was not complete, the engine may always use oil or make some strange ticking sounds since things did not totally "break in".
The same thing was true with the race engines. We ran them on an engine stand for the initial break-in and then changed it oil. I can tell stories (I am sure Pat can also share similar stories) where we were running late and stuck the new engine directly into the race car. Then, drive the car a few miles on the street to get it broke in and loaded in on the trailer. Some people loved seeing that race car coming down the road (including a couple of cops we knew) and some people hated it. Just the fun and games from way back then. I doubt it is done that way today.