1931 Tudor. I replaced the exhaust and intake mann
Whenever you change manifolds, you will have to check them to be sure they are lined up properly. Chances are pretty good that they will not line up because most used manifolds have been decked at some point in their life. Remove the manifolds and leave the intake bolted to the exhaust. Take them to a shop that does engine work and they will be able to deck them for you. When they are decked properly, you should be able to lay a straight edge along the block surface and all ports should be at exactly the same height.