M52TU Build
 

Alrite so here it goes. A swap and FI is out of the question due to availible funds. I already have Headers, Dinan Software, Remus Muffler and a Dinan CAI. I am planning on doing an M54 Manifold Swap and UUC Pullies next. After I'm done with those 2 mods, should I start breaking down the cylinder head and upgrading that? (Port & Polish, Slightly bigger valves, Tougher Springs, etc.) I am also considering ZHP Cams. I am almost positive that they are a direct swap, can someone clarify that for me? Also, will I see a significant difference between ZHP and Schrick Cams and if so, which set should I go with and will that power justify the money being spent on the Shricks? I don't think I will upgrade the bottom end of the engine because it seems that the stock internals are fairly strong, or atleast strong enough for an N/A build. After that a good tuner would need to finish everything up and thats about it. Am I missing anything?

Yes, there is a big difference between Schrick and ZHP cams. Go with the Schrick.