i'd apply the sound deadner as much as possible , I did not sure the difference since i never drove it with out. Nice Viper, any other pics?, what year etc, that's on my list as a project in future but i know little about them and particularily what to avoid, i'd like to get something 1995 or older since we get a break on the insurance because we can put them as 'speacial interest vehicles' ........thx...dk