I agree, the current Porsche sport mufflers are 2-in-4 out designs. One pair of outlets are valve actuated to bypass the secondary mufflers. It's a large unit...and very $$$.
To be honest Ben, I have a feeling my 2-in-1-out I just got from you will make my daughter and neighbors happy
But I'll be in touch when I get the itch for more loudness...it always seems to happen a couple years after.
I guess I need to get off my duff and put the car together to find out, right? At least I sold the 911, so that'll give me the $ needed to finish the 914. Leave it to a 914 guy to sell a perfectly good, strong running 911 to fund a 10-year 914/6 conversion project