Quote Originally Posted by PURE jdm View Post
infiniti and nissan's newer engines (vq line mostly) have a silicone/teflon coated pistons and cylinder walls for better heat dispersion and shorter break in period. they recommend no more than 80 during your first 750 miles. and no more than 100 during the first 1200.

RPM isn't really a issue from what i understand (sans redline) but it does provide a bit of insight.
RPM WOULD be the issue, not mph. They just tell people MPH b/c the average joe blow doesnt look at the tachometer. I am sure the coating on the pistons is probably for reducing friction, coating the sleeves would greatly reduce the life span of the engine as the rings are metal and the only thing that touches the cylinder walls anyway.
I am a firm believer on an engine being broken in the same way that it will be driven. If its a race engine, get it to OT, look for issues, scream the guts out of it or if it needs tuning have it tuned before it ever sees the road/track. Putting mileage and rpm cycles to me seem to be complete bullshit. If you build an engine for just daily driving I would put it together, or if its bought new and drive it the way I had intended to drive it.