jasper engine,,they warrenty the engine,,call them and explane the situation....they may work with you on this..

Seen that with hydraulic cam when the valves were lashed to tight.

Sounds like too much timing and detonation and heat. Vortec heads only like about 30* of timing max.

I had it happen on a zz4 350 hp 350 years ago, had a holley pro jection (junk) and it was too lean somewhere, Smitty

jasper engines I've seen and used been nothing but junk ! welded up heads, but good warranty...to much timing...seen that happen with many small blocks..my engine builder says 26 deg max on those..