lack of oil

 

So if an oil pump were to fail on you while you were going full throttle, would that cause a spun bearing pretty much instantly then?

 

it can. a spun bearing is when the main bearing "spins"

when the crank puts too much force on them it will spin. oil reduced the friction between the bearing and crank.

high rpms- more Rpms = more "force" on it. when that bearing spins- the end is near.

 

So if I leave my engine close to stock, and keep the stock 5700rpm shift points, my chances of a spun bearing in the future are pretty low then, correct?

 

When I spun my #1 bearing, the bearing halves were actually both sitting on the bottom of the rod on top of each other. So whenever that cylinder fired, it would know because of the rod getting pulled up and slapping the crank. Mine was also non existant when it was cold, but when it warmed up it was damn loud. And it happened the only time, and I mean only, that I reved it past 4.5k.

 

the further the gap gets b/t the bearing and crank/rod -whatever for that matter- the greater your chances of spinning a bearing

since you aren't going to add material to the bearing this pretty much translate to the more worn the bearing the greater the chances of spinning it. Only time it would get too tight is an imporpper (re)build.

I honestly wouldn't lose sleep over spinning to 6400

 

If your motor is in good shape over revving won't spin a bearing, Lack of oil or Oil pressure will or too close tolerances or getting any coolant in the oil such as a head gasket going, Main bearings will be a different kind of knock than rod bearings, Rod bearings you hear on every stroke, Mains aren't quite so loud and you may hear more on start-up but if you keep driving the car they just get worse intil something breaks.

 

the tighter the tolererance, the better.

You are confusing the words clearance and tolerance

 

Clearance, Thats the word I was looking for