Back in high school the only thing I was savvy enough do was go to the junkyard and buy a bigger engine. Now, with some spare time and 40 years worth of info at my fingertips, the high school kid within me is re-visiting the hobby probably in a fashion that is also 40 years too old. I agree that there are off the shelf parts that will outperform ANYTHING I will ever re-discover, but to be honest, something within me is very challenged and intrigued to maximize the potential of junk! I think I am just learning all the tricks of performance that most of my peers have mastered long ago and are sitting in the back of their minds gathering dust. I had the pleasure of chatting with an engine masters level engine builder, and he commented at one point that roller cams were around near the beginning of the last century, so old tricks never really die. Oops, yeah, grinding that bump out is probably 75% of the available improvement in that exhaust port. Getting real CFM data is costly around here, so you will only get a guess from me!