DAn,
I can't answer your question about the maximum overlap but here's a suggestion on a cam. I've got this one in my engine and I'm pretty happy with it. It's kind of going against some people's ideas about cams but I was able to see dyno sheet comparisons of a couple of different cams installed in the same engine. The peak HP and TQ was virtually the same so I chose the cam that wouldn't put as much stress on the valve train.
I installed it at 0º, ran good but I'm leaving some ponies on the table since I'm only getting to 5100 rpms. This winter I'll be taking a couple things apart so I can reinstall the cam at +4º. That'll lower the peak by about 300 rpms.
ISKY CAMS
Grind No./Type
296 HYDRAULIC High performance use/bracket racing. Good idle. 2800 Stall. . Up to 800 CFM Carb. RPM-Range
2500-6500 Valve Lift - INT .510
EXT .510
Valve Lash Hot - INT .000
EXT .000 ADV Duration -
INT 296°
EXT 296°
.050 Duration -
INT 234°
EXT 234°
Lobe Center 114°