Replaced my Tubi on my 360 spider with the modified 430 exhaust as detailed by Aldous Voice(Great Reference website). Very close to Challenge Stradale System. Started 360, very loud! Bumper not on to allow check for leaks. Both Bypass Valves were open at idle.(They were capped prior). Selenoids appear to be connected OK. System ECU should control open operation at a specified point based on programmed data from my understanding. I appear to be missing something! Input appreciated.