Test you troubleshooting skills
It's caused by two things happening. 1. at WOT and decel after WOT, you aggitate (for a better lack of words) the oil in the top of the motor, around the rockers, causing alot of it to become airborn and some atomize. 2. At those same conditions, you're pulling alot of vacuum, and are then pulling all that aggitated oil through the PCV system, since it draws from the valve covers and the PCV valve (actually the whole system) sits sideways, it's not helping to stop the oil from making it's way into the intake.
Hope this helps!
Matt
That is interesting about the MACs I have never heard of that before. I run them and do not have any noticable smoking.
One thing about the MAC's is the air pump tubes sometimes causing check valve problems through the AIR system. Might want to use block off plates or "restrictor" plates.


