engine combination

was the 347hp to the wheels or flywheel? theirs no way this his car will run high 11's with the combination I have now. I did read in a hot rod magazine where they put this same engine in a 65 valiant and it ran 12.49 (basically same car I have) but it had fender headers and better exhaust. I'm sure I can get a little more out of my combination but not in the 11's like your saying. when I change heads and cam was planning on a dyno tune before taking it to the track (would try to make changes at track but most of the time you can only get in 3 to 4 passes in). I want this car to easily run in the 11's