RE: Engine break-in
I don't know about other break in procedures on other cars..but for mine with 400hp
According to the manual of my car....it is stated not to exceed 55 mph for the first 500 miles. The car had 26 miles on it when I purchased it. I drove mine home 90 mins when i picked it up. I hit speeds of 75 mph not knowing anything about this break in. The sales manager never told me about it. I did not beat it, nor did I get on it, smoke the tires or anything of that nature. I drove it sensible and with great restraint. I now have 21K. I burn no oil between 5K oil changes. I get 25-27 MPG on turnpike and straight freeway driving 65-70mph. I get 18-21 round town and occasional bypass driving. I generally refuel at 1/2 tank and alternate 92 and 89 octane. If the 92 octane at refill is a few cents more than 89 I will use the 92(many times I have seen a 12 cent difference in octane). Manual says it recommends high grade gas. Key word being recommends. It further states 89 octane will not harm the engine but you may experience a slight loss of power at take off. I have not noticed any loss of power. No knocking or anything.
I have read other posts of guys who did not adhere to the 500 mile break in procedure and some burn 1 quart of oil at 3K intervals some burn more. Some get 17-19 mpg at best. Some guys just cannot resist or wait for the games to begin.
IMO I think if you take a new motor out and baby it for the first few hundred miles rings and such should seat properly.
I have been fortunate enough to have had 5 new cars and exercised restraint at break in and I have never had a car burn oil or valve taps or piston slaps or any other problem associated with improper break in. I think the key is drive sensible and take it easy.
Incidentally my first oil change was at 2K. It's all synthetic Mobil 1.