Hey all, I read a lot about reversion, the causes and solutions and cam specs and thought id be ok. After I did the cam break in n pulled manifolds to install inner springs and there were white water spots in the ports.
here are the specs:
351w/393 with stock length rods
cheap Chinese aluminum heads assembled myself
performer rpm intake
600cfm vac secondary holley for now
hy-tek tubular manifolds
cam specs:
.499/.522
220/227 @.050 267/275 advertised
112/109 (cam calls out 112/108 but it degreed in at 109)
Not sure on idle rpm, it was low. maybe 500rpm. will ideally be set to 650 or so.

Should I be looking for a milder cam or adding length to the manifolds? Or will raising the idle to 750 and cracking the throttle after idling/before shutting down keep this thing alive for a few years?

Engine idle rpm (too low) can definately do it. Raise to 800-850 rpm. If still does it, will have to modify exhaust to enter water into exhaust stream later and/or steeper rate if fall.