If memory serves me correctly both the Sy's and Ty's came with 2.5" DP to the cat, then 2.5" out of the cat to the muffler . Then the Ty's went with a 3" tailpipe and the Sy's went with dual 2.25" tailpipes.
Sy's exhaust split after the 2.5" cat connection and went to two mufflers. Both came with Dynomax Super Turbo mufflers.