some highlights;
-bigger valves!
-bigger ports (more flow)
-thinner valve stems (less obstruction)
-superalloy valves (stronger)
-titanium retainers (lighter, stronger)
-round coil springs (won't bind like the stock flat coil inner springs)
-taller springs for more valve travel (can open valves further if desired)
-stronger springs
-everything is off-the-shelf components for easy replacement/repair if necessary
-works with the stock cam, or can use bigger cams since valves now have more travel room
-all intake and exhaust ports polished
-maintains the stock factory ceramic ports
the valves are top quality manley valves;
http://www.manleyperformance.com/
more info on superalloys (better than titanium);
http://en.wikipedia.org/wiki/Superalloy
from the local 951 race cars past experience with similar sized valves, just the head swap alone should add an additional 40 to 60 hp at the wheels, at lower boost levels.
stock valve vs. new valve;
