Quote (DatNiggaJesse @ May 16 2020 01:18am)
I'm confused by your question... a headunit usually puts out about 22-25RMS, you would not be getting anywhere close to 100w.
If your factory amplifier is putting out 45w (not sure how you tested.) then 70w speakers should be perfectly fine. This is where efficiency comes into play with speakers, some get louder off less power, some require more.
Sony puts out high rms head units, sony wx-gs920bh ..scope it out