On a really big cam IDK.
The biggest I have tuned have been the 340/360s with the 292/508's,which were still tuneable with a single PCV, operating as an Idle Air bypass,and using a non-4-corner idle, carb. The Bypass makes it easier to set the T-port sync. Without it, you have to figure out an alternative way to give the engine the idle air she craves. Some guys crack the secondaries, and some guys drill small holes right thru the primary throttle valves, which I prefer.
Don't worry, as soon as you crack the throttle, the manifold vacuum will rise and the PCV will operate normally, helping to keep your engine clean inside..
