AWE Downpipes

Reason:

Shortly after learning about the downpipe upgrade I began to wish for a set of these.

Considerations:

Of the many options available, the following were given serious consideration.

Options:

  • APR – Build quality did not seem as high as those offered by AWE.
  • AWE – Not happy with the taper from 3″ to 2.5″ between the turbos and cats.
  • RS4 – $3000! Too expensive. But would have loved to use an Audi part.
  • Milltek – 200 cpi cats have me concerned about emissions. Very pricey at $1865.
  • Autospeed – Hadn’t even known about these before the Group buy. Based on price alone ($1000) they were worth picking up. The fact that they maintain a 3″ diameter all the way to the connection to the muffler section, where it then tapers, is a nice point given my belief that less resistance in the exhaust system is better.

Decision:

I initially placed an order for a set of APR downpipes. But as it turned out APR was in the process of releasing an updated version and it was going to take several weeks before they would be shipped. I was preparing to move and decided to cancel the order until I had reached my new home. Other things took priority and upgraded DP’s were put on the backburner. I continued to investigate the DP upgrade and two years later when Avalon Motorsports offered a great deal on the Autospeed DP’s as part of a group buy I jumped on the opportunity. Installation challenges diminished my enthusiasm for the ASP DPs and I sold them and purchased AWEs DP set.

I decided early on that I would have the DPs installed for me since all indications were that it was a long and painful process. When I got a quote of under $300 for the job I was convinced.

I took my car in to an Audi dealership that is mod friendly and they performed the install. They had just installed a set of Autospeed DPs two days prior so I was glad to hear they had done an install on this size dps successfully. They told me that it had been a tight fit, but they had gone in.

As it turned out, my DPs suffered from some manufacturing problems also. The end of the downpipe was flared out slightly, which prevented my exhaust pipe extension from slipping over the end of the DP as it should. Using a set of calipers it was apparent that the diameters of the pipes varied slightly between pipes, and even on the same pipe.

A short trim at the end of the pipe solved the flaring out problem and the DPs were successfully installed.

I was happy, until I got home and looked under my car. I saw that the large diameter DPs were uncomfortably close to the ground. Using a measuring stick I determined the clearance with the garage floor to be 2.5″, without anyone in the car.

I spoke with the technician who installed the DPs and they informed me that due to the DP length and width, this was a result. I was told that this was not the case with APR DPs, and as I had an APR chip they suggested I might want to use APR. They also mentioned MTM and AWE as possible alternatives.

After some further consideration, I decided to go with AWE. My initial reluctance to go with a smaller pipe diameter had been replaced with a desire to have well fitting DPs. I had learned while attempting a dual exhaust install that the margin for error was much smaller as the pipes diameters increased.

The AWE DP install went well and I have had no problems during the few weeks the system has been on my car.

Satisfaction:

I am very pleased with the AWE DPs. The fit is good and the quality appears the same. As far as performance gains are concerned, I can hear the turbochargers more now. They “seem” to spool up quicker, but my VAG measurements do not show any recognizable decrease in the time required for boost generation, which I would expect to see if they actually were spooling faster. How about more power? I cannot yet notice a difference, but I am also running an APR v3.3 chip that suffers the timing problems common to this software version.

Long-Term Report:

Without doing empirical testing I cannot make any statements concerning the performance benefit that having the downpipes confers. I can now hear the turbochargers spool up more easily. The fit of these AWE pipes remains excellent.

Audi B5 S4