Why was the crankcase breather connected to vacuum? I see many people running their breather to atmosphere and catching the oil mist using filters, but why wasn't it just done like this from factory? Is it because of emissions? Or is it because its more efficient?
Vacuum is strongest at idle and that's when crankcase pressures are low, so it makes sense to have vacuum assistance at low rpms. When venting to atmosphere, the breather is only really effective at higher RPMs.. do I have that right?
Should I care about venting with vacuum? or just vent to atmosphere and melt the ice caps.
Thanks