u can soundproof on the wall between the front bonnet and cabin, do it from inside bonnet, use good material, i used stp gold
also do doors on the door metal and door trim, fenders can stuff memory foam to block front tyre sound..

improved a lot, but still not as silent as honda city or vios. at most my loudest (increased bass & treble also) stereo volume is 8. rev till 4-5k now like rev to 3k rpm