my exhaust is 4 peices starting at turbo
autobahn88 dump (with a 3" flange welded to the 2.5" one)
front pipe goes from dump to cat
mid section includes cat
and rear section from just behind the dif back (have 2 muffler setups for it a cannon and oval muffler)
obviously it's 3" all the eay through after the dump
once i install the gt3071 i'll make up a 3 inch dump to suit