The Silver B5 S4 that I’ve been working on, referred to as “pig pen” on account of the extensive covering of sandy oil that nearly every surface in and around the engine compartment has, arrived with a few new parts to be installed from XS-Power.

Starting off was the XS-Power Diverter Valves.  They’re shiny but not confidence inspiring.  With the separable components and multiple spring options they struck me as an opportunity for failure compared to the tried and true 710N.

These stayed in the box and a pair of 710N’s went onto the S4.

The next part was the XS-Power bipipe.  I had hopes this part would work out, but the fit was not good.  With the part not fully seated on the throttle body the pipes were contacting the cam covers.

The separation beneath on the bottom side was greater.

Not only did the pipe not fit against the cam covers, the 3 Bar MAP sensor adapter sleeve would not fit into the hole in the XS-Power bipipe.

There was going to be no playing around to try to bend the pipes to make them work, straight to the classified listings I went in search of a used APR Bipipe.  A week later I had an APR bipipe installed and the MAP sensor adapter fit into it as expected – hooray for APR.

XS-Power turbo inlet pipes were next.  A quick test fit onto the compressor housing, with o-rings installed, showed that there was a little side to side play in the pipe.  I saw an intake air leak coming if they were installed as delivered, so out came the saw and off went the ends of the inlet pipes.  A silicone adapter was used to join the inlet pipe to the turbocharger.

At the other end I found that if the support bracket was bolted to the valve cover that on the driver side the inlet sat too low, causing the Y-pipe to also sit low.  So I did away with the bolt and adjusted the inlet pipe as needed.

While the inlet pipes required some work, they were usable.

The last of the XS-Power parts was the full exhaust.  I was pleasantly surprised to find the downpipes fit well, although they are not a full 3″ design but a tapered design so there’s some more room to work with around the transmission mount brackets.

The rest of the exhaust was less pleasant to install.  The rear parts of the exhaust pipe slide over each other which is an okay concept but hard to implement.  The alignment has to be spot on and there is not a whole lot of overlap available.  The outer pipe does not have any relief cuts in it, so the front and back halves fit together very tightly.  So tightly that I was afraid to pound them together for fear of not being able to separate them later if needed.

So the exhaust will need more attention, most likely from a shop specializing in exhausts with the tools to make corrections to this system.

Overall I wasn’t particularly impressed with the XS-Power products.