if you are serious about making power none of those will really help you
i'd worry about building the rotating assembly up before getting a header. i'd most likely throw in some high comp. pistons using some heavy duty bolts, pretty sture stock rods will hold but might want to think about upgrading that, balance it all on a stock crankshaft, use the GSR head with a nice port job, and then get a header/intake/exhaust to match the airflow needs of that compression along with high revolutions (like 10krpm)
not to mention other parts usch as an engine managment system and new fluid delivery systems (fuel/oil/coolant)
if you are looking for I/H/E the money is better spent at driving school learning how to drive correctly. it will shave down the times in any car you drive.
IBanoobsaysit'saheadernotheaders,idiot.