PCM 351 exhaust manifolds

There isn't a good way to pressure test them without taking them apart and making a blank plate to block off the water passages, and then that doesn't test the risers.

One way that will tell you if you have a big internal leak is, with the risers on, to put a 3/4" pipe thread X garden hose thread in the water inlet and turn the hose on full=blast. Have the manifold assembly upright. (in running position)   If water comes out of any of the exhaust dumps, you've got an internal leak. Water will come rushing out of the exhaust outlet, but that's OK. Let it run for a couple of minutes, at least. Note that this is best done with the manifolds OFF the engine.   

I have a pair of used Osco replicas of PCM manifolds, but I don't have any 3" risers.

Let me know if you are still looking for a pair of manifolds. I have a lot of extra parts from an engine swap I just did in my 2005 sv211. Excalibur 330 motor by PCM.

Yeah They were just surface cracks that I did some grinding and filling on. but after all that work I put back on and went to screw in the new drain caps and the threads are completely gone.

Kyle,
Pressure test the ones you have.