360 magnum crate engine question

My neighbor has that engine in his Duster street/strip car meaning full interior,and full exhaust. In Vegas the density altitude is around 2500-3000.His Duster with 4.10's 3,000 converter 727 runs mid 12.40's to 12.70. He has run this 380 crate for the last 10 years and beats the hell out of the car.He does no tuning just runs it. With some TLC it should be running in the 12.20's.
That sounds good thank you