A good many replies have been recommending a zoomy cam. Increasing compression ratio by milling head will make a difference.Octane fuel may become a issue. Good engine performance has a lot to do with how will your engine breathes. A good valve job with balanced push rods new springs etc. etc. Porting and polish head intake and exhaust will allow your engine to breathe smoothly and if you got the $$$ a tuned exhaust header will once again allow her to breathe clean and free. Free flow exhaust attached to it will also get you a bit more h.p.Now getting the fuel injection to perform is another subject I will leave to the experts. I am a machinist who crewed for a few scca formula fords and super vs back in the day. All of the above requires bucks and time to balance jetting to your new set up.You must ask yourself if a 6 cylinder push rod cam engine is really worth the effort. Mike