I don't see this mod adding a lot of power over a true dual exhaust with crossover, but it sure must sound exciting!
One thing though. Pushrods4ever did say that his hearing was impaired after each run for a period of time. That is an almost SURE sign of permanent hearing damage, I'm afraid.
I am very senstive to that right now for reasons that a few of you know about. DON'T hurt your hearing - you won't realize how important it is until you lose some of it. And, the losses tend to be frequency specific sometimes,which fools you because you think you are hearing everyhting the same, but you lose many of the subtle frequencies important to understanding spoken language.
This does not mean you can't use exhaust cutouts. Just wear earplugs or earmuffs when you do. There are even sophsiticated earmuffs with dual (stereo) amplifiers that filter out ONLY sounds that are loud enough t be harmful, and leave the rest alone. With these, you can also AMPLIFY the "non-harmful" sounds, so that someone's whisper quite a distance away can be heard. Dillon (shooting accessory and reloading equipment supplier) makes a good set that I ahve used for years.