Two things that I noticed. Some of the Australian aluminum heads as of recent strongly resemble the ports on the A3 heads.
With a nice 3 angle "valve job" they flow 330 cfm at .600" of lift. You can extrapolate that almost proportionally with that head to about .800" lift.
If you are a racer attempting to milk every last drop of horsepower out of the heads and if you found a head better, it wouldn't be drastically better.
It's a good head.
That entire series of heads, the A3, the B351, the C302, the D and all of the improved castings that follow them are highly sought after.
The A3's tend to be better for larger than 5.7 liter engines.
All of the engine builders will tell you that in "their" experiences one is better than the other BUT there isn't one of them that will turn down a set of A3's unless they were seriously hurt, and the nature of the repair would be questionable for the durability of the thing?
Which one is better is just an academic debate and SOMETIMES the term better needs to be defined or qualified first?
The block you can't know until you disassemble the engine and examine it. Some of those blocks had core shift and some show about .100" OR LESS at STOCK bore dimensions on the thrust part of the cylinder bore.
Even still you could probably sell it in the $4000 range without the buyer even coming to look at it. Simply put. It's a very desirable block.
What would be nice with this engine is that it wouldn't take much at all to detune it a bit for a street car. Probably just put a civilized camshaft in it?
I personally would not run titanium valves on the street but there are those that are doing it.