vent the new caps up wrench
Mopar use to advice that, drill several vent holes in those early caps, on all the Mopar caps using any of the MSD race boxes thumbs
I would drill 4 1/4 inch holes between every other spark plug wire terminal up Some guys would drill the sides, any thing was better than no holes to vent the air out of the cap shruggy

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)