im 15 and working partime and trying to take mechanics the other part. so in mainly working off of old junk car and stuff from boneyards with the occasional mail order from jegs or summit racing. what im doing right now is putting on headers and dual flowmaster exaust that is going to exit about 8 inches behind the front wheel. so after i upgrade the exaust i want to upgrade the intake and carb. i think i will go with a 625 cfm holly and the edlebrock performer 390 manifold that i mentioned above, what do you guys think about that combo? and what would the cheapest and simpleist way to crank out 400 hp (i HATE nos, and dont like EFI)