I am running the 2.5 block with 2.0 heads on the 2.0 block there is only the one crankcase vent but on the 2.5 there are two , At this time I have the second one caped off . But I am thinking about putting a crankcase breather on it instead of capping it! Has anyone done this and will it effect anything other than having better crankcase ventilation?
I am a noob.... but I would think that if you didn't tie the second breather back into the intake like the single breather on the 2.0 block, you might have some problems. The breather on the 2.0 block creates a negative pressure in the crankcase and you might pull air in the second breather if it isn't tied back to the same negative pressure. Hopefully that makes sense. That is my $0.02