Well one point that we can all agree on is the bottom end is alot stronger than any b series block. The stout girdle is a plus. Now I have looked at both the d16a6 head and the b16 series head...mainly to decide which way I was going to go with my build. I did find something interesting in that research. The d16a6 head has better flow potential than the DOHC versions and the b16 versions. Mainly due to the shorter intake runners the SOHC head has. Port them and port maych to a high flow intake manifold and you have a real breather. From other sources it has been noted that honda engines thrive off of air flow. As Can be seen by the numbers layed down on dynos from turbo powered hondas. If this were true the shorter the runner the faster the intake charge, a larger and shorter runner would equal a faster/larger intake charge. Keeping in mind that an engine is no more than an air pump. Hence more air/ fuel more hp/torque.
So, a d16a6 head worked over,(i.e, port polished and matched, oversized intake and exhaust valves, and the right cam, which can all be done for under $400 if you have the right people in your pocket) Can turn into a real fire breather....
And that not even dipping into the bottom end, which will already stock support massive gains in hp/torque.
If I am wrong with any of this please let me know.
Still learning about hondas myself... and I am by no means an expert...just doing the math.