Restrictions. No doubt. So looking at the heads, they are easy to free up. I realized instantly that the engine needed a bit larger valves, so I went and had some made. That turned out to be cheaper and better than buying stock ones.

Rebuild kit prices plummeted this last year so that helps, suddenly it is in a typical budget to rebuild one.

So far, larger valves combined with port changes and a better exhaust seems to add a nice 30-35 H/P easily.

So like all engines, she responds to airflow. Free up the intake and exhaust, bit of port and valve improvement, and I see a nice 20% plus gain in there.

So far Tod has only done a half dozen or so but it seems to work real nice, I agree with Tim over at DOA. There is 20-30 easy ponies in there, much more gets you reaching deep in the jeans for the hardearned......*EB