Could have sworn this has all been covered before, there are sound clips on youbtube of my car as well as the croctoberfest footage, the Capristo is closest to stock in terms of idle volume as measured by a db meter, the tone, however is different. When younstart the car it depends on whether or not there is any vacuum in the lines still but typically there isn't so they start open then the vacuum comes up and they close with a half second to one second and remain closed while the engine runs and the computer doesn't change anything. Of course a you drive they may come open depending upon the conditions and programming thresholds. If you did NOT hook up the vacuum lines they would be OPEN all the time and probably too loud for most people for regular driving.Hi:
How does Capristo exhaust with valves closed compare to the stock exhaust?
If I do not install the vacuum lines, are the valves closed or open? What is the default and starting mode?