|
Hi
no offence taken. i was only quoting from someone how has making very successful exhausts for over thirty years. his exhausts have been on many winning cars. he understands noise suppression round silencers are quieter than an oval of same length. two silencers will be quieter than one obviously. as noise from exhausts are being checked at comperation level he has to keep pace with these changes. limit is 70 desibels. not sure how loud new cars are. aftermarket exhausts are now made alot quiter and still make performance increases. looking underneath my wife's 3.0 subaru legacy has at least 3 silncers and 3 cats but still get alot of performance and 30+mpg average despite having auto box and permement 4wd. so subaru must of engineered a brillent exhaust system. as a previous poster said you can use a more modern exhaust for quietness and performance. bottom line is not to increase pipe diameter or you will lose power and mpg. suggest you do some reserach on internet for building exhausts.
|