That is plenty... most performance exhausts such as corsa using a single inlet dual exit exhaust run a 3" pipe up front with 2 1/4-1/2" tailpipes. Is there a reason you do not want to run a x-over pipe? Doing so will make it easier to tune as it provides for a more equal/consistent back pressure for all cylinders. Just something to consider.
Sorry I didn't catch the dual in dual out muffler... this accomplishes the same thing as a x-over pipe. Guess this is the downside of using my phone to access the forum.
Sorry I didn't catch the dual in dual out muffler... this accomplishes the same thing as a x-over pipe. Guess this is the downside of using my phone to access the forum.