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Exhaust - Downpipes - JHM B6-A4 and C5-A6 3.0L Stainless Steel, 2.5 inches w/ High-Flow Cats



Sale Price $1,044.95

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As many of our customers know, we have been working towards the release of the JHM B6-A4 3.0L V6 Downpipes for a long time. After lots of prototyping, testing, trips to the track, and re-prototyping, and re-testing, we are proud to announce that our B6-A4 3.0L V6 2.5 inch Downpipes with high-flow cats are ready to sell!


Why 2.5 inch piping diameter?


We tested a few different piping sizes (2.25, 2.5, and 2.75) and found that in every configuration - stock ECU calibration with a stock sized (54mm) cat-back, stock ECU calibration with an aftermarket cat-back, JHM Tuned ECU with a stock sized cat-back, and JHM Tuned ECU with a stock cat-back - that 2.5 inch piping diameter provided the best gains in acceleration and high-end power without sacrificing low-end torque.


If you are looking to unlock the potential of your 3.0L V6, these 2.5" downpipes are the key. They are an absolute MUST for anyone looking to get more power out of their car. Our extensive research proved this point time and time again. When we put our 2.5" downpipes on a stock car, the car was impressive and the increased airflow of the downpipes definitely made the car seem a bit more "peppy". However, when we put the downpipes on a car with a JHM B6-A4 3.0L V6 ECU Tune on it, the result was amazing. The combination of the increased airflow from the downpipes and the ability of the JHM ECU Tuning to take advantage of that increased airflow completely transformed the power band of the car. The gains in low-end torque were good but the most impressive power increase can be found in the top-end of the RPM range. With the motor breathing more freely and the addition of our ECU Tuning, the 3.0L just keeps accelerating up top!


The biggest gain in power comes from removing the huge catalytic converter complex that Audi has placed right up against the head of the motor, just after the outlet of the exhaust manifold.


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Audi Exhaust - Downpipes B6-A4 3.0L Stainless Steel, 2.5 inches


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Audi Exhaust - Downpipes B6-A4 3.0L Stainless Steel, 2.5 inches


Look at the size and location of that cat! This drastically slows down the airflow coming out of the motor and creates heat - both of which are bad for making power. By removing the catalytic converter AND increasing the piping diameter to 2.5", we solve both of those issues! Actually, the inner diameter of the JHM Downpipe at the inlet is over 2.5 inches!


Click to enlarge picture
Audi Exhaust - Downpipes B6-A4 3.0L Stainless Steel, 2.5 inches


Click to enlarge picture
Audi Exhaust - Downpipes B6-A4 3.0L Stainless Steel, 2.5 inches


These are the same style downpipes that were featured on our record setting, "JHM3LTR", our in-house B6-A4 3.0L V6. See them in action in the video below. It also provides some great sound clips of different exhaust configurations!



Our JHM B6-A4 3.0L downpipes have a reducer at the end of the pipes that will allow you to run these pipes with a few different cat-back setups:
- Stock B6-A4 3.0L V6
- Stock B6-S4 Cat-Back
- ANY Brand X B6-S4 Cat-Back designed to mate up to stock downpipes
- Full 2.5" for JHM-FI B6-S4 Cat-back (cut off the 2.125" neck down and adapat as needed)


In our testing of different exhaust setups and in our experience with cat-backs for the B6-S4, all aftermarket cat-backs neck down to the stock piping size EXCEPT for the JHM/Fast Intentions 2.5 inch cat-back. So, if you have a stock cat-back or pretty much any other aftermarket cat-back our JHM 2.5" downpipes will bolt right up to your system! Just secure your downpipe to cat-back connection with your OEM downpipe to cat-back clamps. If you need OEM downpipe to cat-back clamps, we sell them in our store. Just search for "clamp 54mm".


**Note: If you are interested in running a full, 2.5 inch exhaust setup you just need to cut off the 2.125" reduction that bolts to the factory cat back and adapt as needed.**


- 1x Pair of JHM 2.5 inch Downpipes with High-Flow Catalytic Converters w OEM 2.125" CB connection


- ALL quattro B6-A4s - 2002 to 2005 - with the 3.0L V6 (Manual or Automatic Transmission)


THESE DOWNPIPES ARE FOR OFF-ROAD USE ONLY!!! Like any downpipe that replaces or modifies your OEM Catalytic Converter, these downpipes are not intended for use on public roads. Please consult your local DMV for regulations specific to your region, state, town, municipality, etc...


NOTE: International shipments may require additional shipping fees. Please contact us for quotes. If you place the order through the website we may contact you if any additional shipping fees are required.


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This product fits the following vehicles:
Make Model Chassis Engine
Audi A4 B6 (2002-2005) 3.0l V6 30v
Audi A6 C5 (1998-2004) 3.0l V6 30v
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Off-road Use

By Purchasing any Off-Road use ONLY products from JH Motorsports, Inc. I acknowledge and understand the following disclosure. (This notice is located at the bottom of the page description of affected products on our website.)

Vehicle Code § 27156:
(b) No person shall operate or leave standing upon a highway a motor vehicle that is required to be equipped with a motor vehicle pollution control device under Part 5 (commencing with Section 43000) of Division 26 of the Health and Safety Code or any other certified motor vehicle pollution control device required by any other state law or any rule or regulation adopted pursuant to that law, or required to be equipped with a motor vehicle pollution control device pursuant to the National Emission Standards Act (42 U.S.C. Secs. 7521 to 7550, inclusive) and the standards and regulations adopted pursuant to that federal act, unless the motor vehicle is equipped with the required motor vehicle pollution control device that is correctly installed and in operating condition. No person shall disconnect, modify, or alter any such required device.
(c) No person shall install, sell, offer for sale, or advertise any device, apparatus, or mechanism intended for use with, or as a part of, a required motor vehicle pollution control device or system that alters or modifies the original design or performance of the motor vehicle pollution control device or system.

Health and Safety Code § 43000:
43001. The provisions of this part shall not apply to:
(a) Racing vehicles.

As the aforementioned code sections outline, it is against the law to operate or use a vehicle on public streets or highways with modified, altered, or disconnected motor vehicle pollution control devices. This may include but is not limited to, Evaporative Fuel Controls, Catalysts, DPF, PTOX, PCV Systems, Exhaust Gas Recirculation Systems, Oxygen Sensors, Thermostatic Air Cleaners, Air Intake Systems, Fuel Injectors, Regulators, Adjustable Cam Gears, ECU Programming, Mapping, or other Computer Modifications. Air Pumps, Air Injection, Timing, and any other Emission System Modification(s).

Purchaser acknowledges and certifies to JH Motorsports Inc., that Purchasers vehicle will only be used for racing applications or off road vehicle use only. Purchaser requests these modifications for the purpose of enhancing the vehicle for competitive Racing Applications and will not use this vehicle on public streets or highways. Purchaser agrees to indemnify JH Motorsports Inc., all employees, officers, owners, and subsidiaries for any civil or criminal liability arising out of use of Purchasers vehicle on public streets or highways as Purchaser has been duly notified of the laws and regulations regarding disconnecting, alteration, or modification of a vehicle’s pollution control devices. Purchaser understands and has been advised the driving of a vehicle on public streets or highways could result in criminal or civil penalties.

Prop 65

Warning: This product may contain a chemical known to the State of California to cause cancer, birth defects, or other reproductive harm.

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