Spied: Audi RSQ5 or SQ5 mule caught testing

Our spy photographers managed to catch a first glimpse of what appears to be either an Audi RSQ5 or SQ5 test mule. Although the vehicle may appear to be a run-of-the-mill Q5 TDI, the obvious quad exhausts and quattro GmbH "HN" license plates hint at something much hotter under the hood of this SUV. More photos and details after the jump.

Before we dissect the spy shots, we'll point out that it's becoming more apparent that Audi is working on an S or RS version of the Q5. Citing Car and Driver's report that Audi registered both the SQ5 and RSQ5 monikers in January, as well as Fourtitude's confirmation that "there's more to come in the performance department of Audi's hot-selling Q5," we think this mule is an early prototype of one or the other.

So is this an SQ5 or RSQ5? Well, the quad exhaust is a tell-tale sign of a more potent powerplant than both the stock TFSI and TDI's two-tip exhaust (note how the four pipes do not fit the stock rear valence), which could be a characteristic of either. Although, despite the lack of aggressive RS styling cues, the "HN" license plates reveal that this is most likely a quattro GmbH test mule; suggesting that this Q5 has RS roots (A and S mules typically wear "IN" Ingolstadt plates, RS mules carry "HN" Heilbronn plates). We only wish we had photos of the front fascia, as we're curious of larger air vents. So for the time being, we'll have to refer to this mule as an S/RS Q5.

While still shrouded in mystery, we can't help but speculate to what's under the hood. In our opinion, the S4's 333-hp 3.0 TFSI would be a great match for a SQ5 and the upcoming 4.0 TFSI biturbo V8 with north of 400-hp for the RSQ5. But keep in mind, until official confirmation, this is purely speculation. We'll be sure to keep our eyes and ears open for further developments.