Raced for 7 years in my 340 Cuda, and I bought the big block Cuda while I still had the '72 with the 340. So I would run the tried and proven '72 Cuda in full competition of Friday nights in Pro, and then switch to the big block Cuda on Saturdays in the 1/4mi also in Pro.
During the last couple years I ran the two of them, I raced 2-3 times per week. Had a lot of passes on the 340, and I mean a lot and enough passes on the big block that it didn't make it the season. My average reaction time for the last season I ran, including all the bone head hurry up and leave lights, I still netted a 0.544 ave or a 0.044 by the way they do it today. Generally, on a friday night, I was in the 0.025 or better range on the lights for 1st pass. If you didn't get at least an .025 light, you were dead. Not many cars in Pro wanted to line up against the black Cuda, only the seasoned vetrens.
340 was dyno'd at 337hp, and 400ftlbs with 8.5:1 340 484 hyd cam and 800cfm holley and 904 with 4700 stall and went 12.0's at 112mph and 7.62 in the 1/8th at 89mph 60ft was a 1.607s