too much pressure in motor?

My 88 mustang has to much pressure in the lifter valley at high rpms the pcv valve will relrase tons of oil into my intake causing my car to blow lots of black smoke. I have done a compression test and every cyclendar had 150# to 155# of pressure. So i dont think iam getting the problem from blow bye. What else could cause so much pressure in the motor? Also some times my motor will not run right under 2000 rpms, it will shake and shutter and sound like it is sputtering it feels like it is loading up with too much fuel to soon. But other times it will run perfect and there is no hesitation or sputtering at all. My fuel pressure seems very speratic also. It is any ware from 30# to 40#. Thanks for the help Saleenstang88.