what causes high crankcase pressure? i had alotof oil leaks on my fresh motor, i would fix one and something else would start leaking, i finnally figured out it was high crankcase pressure when i pulled my dipstick and it had pressure, i think i got it fixed by putting a valve cover breather on it, and keeping the other side a pvc valve.

 

That's correct. You probably got it fixed by putting the breather on.

 

i know i fixed it with that, but my previous 305 didnt do that, is it just natuarl with the bigger bore and longer stroke of the 400 or could there be something worng? thanks