what cam to use??

[gmc2u]

Did you follow the break in procedure for a new cam? Usually something like keep idle above 1,000 rpm for 1st 30 minutes. Also I’d go with Comp cams 260 or 268 both are very good torque cams.

 

[68post]

Are the bad lifters always in the same position, or same bank ? What did the rest of your lifters look like after the first go around ?

One of the Valvoline VR oils is a street oil only,(so low in Z,M,P) but I assume you've done the research already. I'd use a different break-in procedure for sure. I wouldn't automatically assume it's the cam's fault, or lifters.