Engine leaning out at 3000rpm

They are brass terminals it is an msd pro billet distributer i changed the cap and rotor it is still doing it intermittenly the msd tech guy said a coil can ohm good and still be to weak to fire at higher loads so i guess i will buy another coil and see if it works it would make sense if it was the coil i did let a ratchet short against the positive terminal once while adjusting timing but it ran great for a while after that so im stumped