New to 340 so I have questions

There is a difference in X’s heads compared to J’s. For most people it will never matter, but here it is. The X’s were cast with the bigger valve in mind, so more clearance from the water passage, while the J’s were not. So in a pretty serious port job. You can get a bit over 10 cfm more out of an X head. Again, won’t matter to many people. Is the air filter an K&N filter? It looks like it needs to be cleaned or replaced.