You really should search the forum man.These topic been covered alot.
But headers comes down to 4-1 or 4-2-1.They are the most common.
4-1 are said to give better high rpm power where as 4-2-1 will give a broad increase through the revs.
Ecu is a whole story in itself.For basic intake,header,catback a vafc or emanage are ok to dial in the fuel settings to suit the mods.

