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ER 1.8T Test Pipe - Audi A4 (B6)


The factory (OEM) downpipe is very restrictive on the exhaust flow in the exhaust system.  Exhaust gas exiting out of the catatylic converter must pass through small tubing in the OEM downpipe which restrict flow and cause turbulence which in turn hinder performance. By swapping the downpipe with the Evolution Racewerks Test Pipe, power is unleashed!  Our Test Pipe improves flow after the catatylic converter by improving flow and reduce turbulence with larger piping.

CAUTION: This product is intended for OFF ROAD USE ONLY. Not legal for use on pollution controlled vehicles upon public road/highways.  THIS ITEM IS NOT FOR SALE, INSTALLATION, OR USE ON LICENSED VEHICLES IN ALL 50 STATES.  In addition to vehicle use verification, a Vehicle Compliance Waiver needs to be signed.

The item is for sale for international customers without restriction.

Ease of Installation: (1 Easy, 5 Hard): 3



Key Features:

  1. High grade 304 stainless steel material is used throughout our test pipe.  
  2. 100% TIG welded with stainless steel welding rod.
  3. Mandrel Bent Piping
  4. Mirror polish or brushed finish available.
  5. 3" Diameter piping 
  6. Smooth transitions to 2.5" to match aftermarket or factory exhaust systems.
  7. Welded both inside and outside of the flanges for strength and longevity.
  8. Includes downpipe gasket!
  9. Includes all hardware needed to install.
  10. Limited Lifetime Warranty.
Our test pipe features a 3" design that reduces to 2.5" (to bolt up to OEM and most aftermarket exhaust systems). Also, we use a "flare" type reducer to reduce the size to 2.5" instead of the "step" type reducer (the "flare" type cost us more to manufacture though). The advantages of the "flare" reducer is that it has a nice smooth transition which causes less turbulence than the step type reducer, therefore producing more power. Also, having the transition as far as possible to the turbo improves performance as well.

The Evolution Racewerks Test Pipe is completely constructed from quality 304 stainless steel and is polished to a mirror finish. The piping is fully mandrel bent.  Our test pipes are 100% TIG welded for quality and strength.  The flanges are welded inside and outside to the pipe for added strength and extra longevity.  




TIG welded flanges




TIG welded inside of the flanges

True to ER standards that our current customers enjoy, EVERYTHING needed for installation is included.  That includes downpipe inlet gasket, EVERY bolt, nut and washer that is on the catalystic converter/test pipe is replaced with high quality full stainless steel bolts, nuts, and washers!  Yes that's right FULL stainless steel, down to even the hardware.  The gaskets and full stainless steel hardware alone is worth $50! 

CAUTION: This product is intended for OFF ROAD USE ONLY. Use of this product upon public highways is prohibited.

Tags: 2002 , 2003 , 2004 , 2005 , A4 , Audi