Here is my best shot at answering your questions...
A bad break-in? Well these days the chances of a bad break-in are slim to none. In the old days when the tolerances were weaker, you could have oil leaks, gasket problems, etc. Engines are built a lot better these days...
Speed? Speed really doesn't have anything to do with break-in, well it does sort of. Don't push the car above 4000 rpm and your fine. So if the gearing allows it, go 200 MPH, as long as you don't go above 4k rpm.
Octane? Well, most cars these days have anti-knock sensors which will retard engine timing to prevent premature ignition. Adding high-octane gas, if the engine is properly designed for it and can use it, should give you a couple more horsepower. However, putting in 87 versus 92 shouldn't have an adverse affect on the breakin.
A bad break-in? Well these days the chances of a bad break-in are slim to none. In the old days when the tolerances were weaker, you could have oil leaks, gasket problems, etc. Engines are built a lot better these days...
Speed? Speed really doesn't have anything to do with break-in, well it does sort of. Don't push the car above 4000 rpm and your fine. So if the gearing allows it, go 200 MPH, as long as you don't go above 4k rpm.
Octane? Well, most cars these days have anti-knock sensors which will retard engine timing to prevent premature ignition. Adding high-octane gas, if the engine is properly designed for it and can use it, should give you a couple more horsepower. However, putting in 87 versus 92 shouldn't have an adverse affect on the breakin.
