42DD MK4 1.8T 3" Downpipe

Bolt-on more horsepower, torque and boost response! Replacing the factory downpipe and catalytic converter is an important step when upgrading any 1.8T. The factory downpipe and cat is incredibly restrictive. Reducing backpressure at the turbo exit instantly increases turbo response, horsepower and torque. Since the 1.8T first hit the streets, performance shops and enthusiasts have proven that downpipe upgrades provide a healthy power increase. Internet rumors and opinions say 2.5" downpipes are "better" than 3" downpipes. We choose 3" for maximum gains. Why not go all out?

Our 3" downpipe begins at the turbo with a CNC machined turbo flange. A custom transition pressed from 1/8" thick steel provides a smooth reduction to 3" piping. This transition is overkill, absorbing heat from the turbo and preventing metal fatigue. Our piping is mandrel bent in one piece to add strength and eliminate unnecessary welds. A stainless steel flex section is used to absorb engine movement. After the flex section a CNC machined flange allows a 3" high-flow cat or test pipe to be installed. We use a Magnaflow 200 cell metal catalytic converter in a spun stainless steel body. After the cat, custom adaptors allow perfect bolt-on fitment to any aftermarket cat-back. We offer adaptors for stock exhaust, 2.5" and 3" cat-backs. The whole downpipe bolts together with locking hardware and double layer graphite gaskets. Precision components and meticulous fabrication ensures zero leaks and zero problems.

The modular nature of our downpipe allows the user to change configurations at any time. For example, let's profile a hypothetical customer. The vehicle is a 2005 GTI with stock exhaust. The customer purchases our street series downpipe with the stock adaptor. The next summer he discovers the local drag strip and purchases our test pipe to gain some speed on the track. Later, he decides to install a 2.5" cat-back. By purchasing our 2.5" adaptor the customer can install the exhaust without additional adaptors, completely avoiding unnecessary restrictions. At any time he can reinstall the cat or stock exhaust by simply swapping out hardware.

Our 3" downpipe is available in 6 configurations. Street series downpipes include a Magnaflow high-flow cat. Race series downpipes include a test pipe. Each downpipe includes a cat-back adaptor available in stock size (2.15"), 2.5" and 3". Each downpipe is shipped complete with everything needed for installation. Additional accessories and hardware can be purchased separately at any time. All configurations can be purchased ceramic coated.

Construction Highlights

  • CNC mandrel bent 14 gauge aluminized steel tubing
  • CNC machined 1018 cold roll steel flanges
  • Professional TIG welded construction throughout
  • 409 stainless steel 200 cell metal catalytic converter
  • Stainless steel braided flex section
  • Double layer graphite gaskets
  • Grade 5 locking hardware

Fitment Details

  • Fits 1999-2005 VW mk4 Golf, Jetta, GTI 1.8T
  • Fits 2000-2006 Audi TT 180 FWD
  • Fits VW New Beetle 1.8T
  • This downpipe will NOT fit any Passat or Audi A4
  • Available in street or race configuration
  • Choice of 3 adaptors allow unrestricted fitment to any cat-back

Starting at: $479.00

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Starting at: $479.00

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  • Model: EX-04-01X
  • Manufactured by: 42 Draft Designs

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  • +1(856)456-3335
  • Hainesport, NJ 08036
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