Considering getting this exhaust and I've been trying to look for Piping size in inches for this exhaust but have been unable to find any info on it, anyone with this exhaust know what size piping it has? If I plan on going FI in the future, would the SMR be a good choice for an exhaust? Also what would be a good Y-pipe to use with this exhaust that has 3-3.5" piping?