Big block exhaust is still loud
3 things about exhaust noise :
i. the further rearwards the mufflers are, the quieter the exhaust will be.
ii. the bigger the muffler case dimensions, the quieter the exhaust will be.
iii. after the mufflers, stepping down to a smaller pipe diameter will not hurt HP. By that time the gases will have cooled and
contracted, thereby not requiring a 3" pipe. Going to a 2.5" OD pipe will likely not show a loss over the 3" after the the rear end.
The Vizard exhaust design works, BUT given the amount of real estate available under our MoPars....very difficult to replicate easily.