Thermoquad idle issue

This 1972 340 block and heads sat in the basement since the mid 80's. I built it from the bottom up with all new internals, crank, rods and pistons last year. Block was bored 40 over standard machine work was done. No deck cutting and heads were machined for new valves 2.02. Stock intake was not cut either just checked for cracks and squared.
Hydraulic Flat Tappet Comp Cam 260H, duration 260/260, Lift .440/.440 with 901-16 spring kit.
Cam break in when perfectly, high zinc, drained after 30 min run. Engine ran better during break in then now. Rings should be set with 500 mi on the motor.