Here's a cold start video of my Whipple Tuned 2017 Ford Raptor with the SPD Performance 3.5L EcoBoost Trombone Equal Length Resonator Delete, RDFR20EL
Definitely louder on cold-startup than with the Flowmaster Flow-FX. The truck sounds like a race car when you floor it, and really screams! There is some drone from 1,800-2,200 rpm so I'm not happy with that as that is cruising RPM around town.
