As per the above - what is is I require. UK MY98 turbo with all standard equipment at the moment appart from afterburner backbox (not vortex.) I heard that the next best move is to remove the front cat. is this true?

 

Up-pipe is from the engine up to the turbo.

Downpipe is from the turbo to your exhaust system.

Most people replace the downpipe with an item that doesnt have a cat. You should then consider some form of remap / boost control to get the fueling and boost set correctly so as not to damage the engine.

Conrad