The new A5201 evoheader for the VW A5 Rabbit/Jetta cars is the second release in our exclusive and comprehensive bolt-on high performance engine development program for the 2.5-liter DOHC 20V 5-cyl. engine. This is not your average header design, it is a true breakthrough not only in the VW performance scene, but in the automotive exhaust industry for many reasons. Using the latest real-time precision exhaust header design technology, we created a very unique and compact header system with features found typically in much more expensive applications. The result is a high performance system of tuned tubes that is effective not only in scavenging spent gases, but noticeably improving the filling of cylinders with fresh intake charge by inducing a natural resonance for the columns of exiting gases at specific rpm points to maximize power and torque. And it fits past the cylinder head and extended lower windshield edge for a bolt-on installation.
The A5201 evoheader, like all our products, started with a clean sheet of paper, and a tall order of required specifications. Our main objective was to give the engine the required scavenging and free flowing characteristics to take advantage of what is to come from Evolution tuning in the next months. In the process, we ended up gaining power and torque at this early stage of our engine development program (with the A5301 evoair intake as the only other release). Here is a summary of the key design features:
 

• Super-compact, equal-length and tuned, 5-into-1 tubular exhaust header design that promotes a resonance condition in the exhaust gas columns for a flat mid-range torque curve.

• Ample 1-5/8" OD primary runners for strong mid-range and top-end power gains, with enough room to accommodate upcoming Evolution tuning performance engine product releases.

• Primary tubes enter the exclusive header collector following the engine's firing order and thus, creating a natural, high-velocity and permanent swirl-like discharge of exhaust gas gases down the pipe. This results in a highly efficient scavenging of gases plus a much improved filling of cylinders with fresh charge even at low engine speeds thanks to the wave-action tuning.

• Super-compact header design for maximum heat retention and total bolt-on fitment (no modification is required), hand-crafted entirely in stainless steel 304 and TIG-welded for a superb appearance.

• Improved orientation of header's downpipe flange to the factory flexible downpipe for a smooth gas transition.

• Industry-exclusive, ultra-short, 1-piece, smooth 5-into-1 collector with provision for the stock O2 sensor.

• New OEM metal gaskets and hardware included.

• Designed, engineered and made in USA.

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Our test car was all original, with the factory exhaust system and factory software plus regular  87 pump gas. All the reported gains come from the installation of both the A5301 and the A5201 products alone, and no other change. Due to the varying nature of power values read from dyno to dyno, these numbers are more useful if viewed as "before and after" gains rather than absolute gains.

NOTE: For international customers (outside the US), please email us your order BEFORE sending money, so shipping costs to your country can be estimated. Thank you.

All rights reserved. Evolution tuning, Inc. 2007. Updated March 24th.2008.