have a set of ported X heads on my 340, engine builder said they have better flow numbers, then out of the box $2400 dollar edelbrocks and i only spent 1/4 the money in them , and edelbrocks first thing you do is replace the springs, and 7 degree locks and retainers. edelbrocks are 40 lbs lighter per head it just what ever you want ,that was just the engine builders opinion
