IIRC the valve centerline is moved to the bore center. Look closely at the head pics posted. They have a 1/2" wide ledge right below the bottom row of head studs. The 440-1 does not have this. Thats roughly the amount the valves are moved. Even if it's not the 13 degree valve angle would require custom pistons. Stock is 15 degree. if you have pistons that are cut for significantly larger valves than 2.19/1.81 you could get away without custom pistons, but I'd think the steeper valve angle would be problematic otherwise.
2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
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