dual mass flywheel

I have noticed that it seems like all clutch replacements for a 2018+ mustang all come with lighter flywheels that are aluminum. Why is this the case? The OEM duel mass flywheel is steel but every manufacturer seems to use a single mass aluminum flywheel to replace the OEM one. Any one have...

I have a 2016 Mustang GT with an x pipe delete and roush mufflers. Previous owner did that. I’ve had issues going 65-80mph and up I have shaking in the pedal and in the wheel as well as car itself. Engine sometimes stalls when in neutral at red lights as well. Sometimes have issues with idle...