A Decent 6.5inch 2 way component setup properly mounted is what you need.
I tend not to use the plastic adapters you can get as they rattle like hell. I mounted mine on adaptors I made myself using MDF. I also Put a layer of dynamat between mount and door and between speaker and mount. I used a set of JL components and they sound mint.

You won't get that good quality deep sound without some sort of sub though. Have you looked at the under seat ones? They are unseen and just add that crisp quality bottom end.

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605whp
Quarter Mile in 10.9 seconds @ 135mph /217kph
0-100 kph 3.2 seconds