Ooh I'd draw something in paint but I'm too lazy.

Basically on our cars, we've got the manifold, then the turbo, then the cat, then the downpipe followed by a bit of flex pipe and then the rest of the exhaust.

Downpipes don't really need a fancy name... it's just another piece of pipe, that has a bend in it. It's the piece that travels "down" through the engine bay after the cat, and eventually bends so it's parallel with the ground.

EDIT, and a test pipe is just a hollow pipe, opposed to a catalytic converter. You pollute like a bastard with a test pipe, but you gain some power because the cat obviously restricts exhaust flow. I've got a compromise with an HFC (high-flow cat). So guys who run test pipes have the following:
Manifold, turbo, test pipe, down pipe... then rest of the exhaust.

 

okay thanks man, lets keep this convo a secret. . . i dont want the other guys around teh board to make fun of me haha kidding!

 

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