I need help on a final decision about a cam

[Dave F]

I prefer the Mechanical secondary. That way your secondary opens on throttle position and not on vac settings.
DAVE

[Thrasher]

Dennis is exactly right about the oval port heads.The smaller intake runner of the 781 producces higher velocity in the port at the R.P.M. that you are working with on your cid
engine. As far as oval ports being junk how does
570 hp on pump gas sound. Dyno sheets avalable.
Thrasher