I had previously experienced some issues with oil getting sucked into my IM via the PCV on track when I lifted from near-redline and threw the car into a hard braking turn. I had already replaced my valve stem seals and passed a leakdown test with no issues. Putting a catch can inline between the PCV valve and the IM revealed it was all coming through there.

So I was still getting this oiling issue, and I decided to use an old gutted PCV into a vented catch can and cap off the vacuum port on the IM. Sure enough, all the oiling problems went away, and the catch can stayed empty.

But now my brakes are softer than they used to be. I replaced the MC, completely flushed the system and re-adjusted everything, but they just feel softer and stop as good as normal otherwise.

I'm starting to think that by plugging the vacuum port on my IM, I created more vacuum pressure on the brake booster, causing it to work really well?

Also, if my compression numbers are all 200-205s, could that mean I have oil in my rings and I need to try a sea-foam treatment? Could the high compression test and high vacuum be related?

 

well, adjusting my idle screw has effected my brake firmness, so I'm imagining that capping off the PCV inlet did indeed put my brake booster in to hyper mode.