downpipe size?
 

hi peeps.im gonna replace my up and downpipe next spring but was wondering,do all downpipes start at 3" coz im looking at a 3" to 2.5" pipe to match the rest of the system.i know you can also get 3" all thru but i take it these should match 3" systems only.its for a bug with standard turbo.also is a sports cat downpipe the way to go?i dont fancy having to put oe cat on every mot day!!!it would mess up the re-map too.(have i just answered my own question lol)

i wanna no the answer to this 2 before i sectionsstart buyin down pipes and center

changing the centre is ok and straight forward but the down and up-pipe will need a re-map to gain full benefit and to be safe on the engine.

bttt

I think the bolt-holes on the centre section's OEM-sized 2.5" flange are elongated "ovals", thus allowing them to line up with a true 3" downpipe flanges' bolt-holes - although don't quote me on this!

If so, then you can also get a bigger 3" donut wirewool gasket to fit in there as well.