You will get drone on most aftermarket exhausts in certain rpm bands. From review, Motordyne has less drone compared to FI (boost lee i believe).
Like everyone says, FI is smoother and deeper, motordyne more aggressive and higher pitch.
If I could do it over again I would do motordyne test pipes with motordyne shockwave. Currently have FI 18" SS exhaust with FI resonated test pipes. It's loud in a good way but can be annoying at freeway crusing speed when rpm band is 2K to 3K.
Added side branch pipes and it calmed the drone down a lot. Testing to see if I like the new setup or if I want to change to motordyne.
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