Just some thing for you to feed on>
Tight means oil is going to get hotter,with that said,we all know what heat does to metal.
Every thing has to work together,oil pump,clearances,etc.rods float on the crank in an oil film,if the oil can't pass between the rods effenciently enough it going to raise oil pressure and make heat so to speak.
Thats why I gave you guide lines,at least thats what I use for a rule of thumb,
maybe some one smarter than me can explain it better :P
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