Any real muffler shop can make you a test pipe to connnect the 2 pieces, but it will most likely be made of 2 1/4" piping to connect smoothly to the exhaust's B-pipe (your Tanabe most likely is 2 1/4"). Are you planning to eventually upgrade to a VTEC head or upgrade the cams in that thing? A CTR header might be a bit overkill for a stock B20.
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Andy - Reinstated
Hybrid Forum Moderator
'06 Subaru Legacy Spec B - Stock, for now
'98 Civic EX - CTR headlights and grill, Kosei K1's, for sale
'90 240SX - SR20DET that will never get installed, project car.