can anyone help me get an extra 200 hp out of my stock 340 what parts do i need to change or what never can get anyone that i talk to with a straight

There are lots of different paths; the main questions are how much money and ruthlessness you're bringing to the party. My own personal preference would be ported heads, mild cam that's just a little more aggressive than stock, fuel injection, and a GT45 or similar sized turbo. Not the cheapest approach, but you can get good drivability and longevity out of a turbo motor if done properly.