[beetle1303]

I would prefer a more "proper" 4-1 system, using a fifth pipe or secondary from the merging flange to the back so it could be tuned a bit. This one looks like having 4 pipes simply flowing into a larger one... From my point of view there is nothing to gain performance wise. Always remember that engineers are faced with another big issue called Packaging". I guess that the closest they could get to a properly merging 4-1 system due to clearence issues with the 356 fitment, so they compromised 550's performance to gain from reduced manufacturing costs of building 1 instead o 2 different exhaust systems. You could keep the general pipe routing idea and build a fully merged system though. Don't get me wrong, but nice is different to "working"

Chris