Try this cam. Comp cams Dual energy 275DEH-10 it is a much better choice for your truck
and will not cause pinging problems. makes lot of truck torque and power and will work very well with your 2500 stall. You'll like this one.. Ditch the old school obsolete Streetmaster intake manifold.
A modern dual plane manifold will do everything better.
The cam is comp cams part # 12-209-2 275-279 219-229 @ .050" .462-.482 110 lsa