Photos surfaced earlier today on Quattroworld of what appears to be an RS 7 test mule shot near Las Vegas. On the surface, this matte black A7 tester features a larger front fascia that, while not far from the chin of the freshly facelifted S5, is both larger and more animated. Taking the image and blowing up the front fascia section (above) reveals a chin identical to the gloss black test mule spied testing in Spain in late May (below).



Even more news (and worth a click through to the Quattroworld report) are additional photos in the set that depict what is believed to be an RS 6 Avant and also Audi's much-anticipated new 4.0 TFSI biturbo V8. To our knowledge, this is the first time either has been seen.

So What Do We Know?
We're pretty sure these are both RS-spec cars hot weather testing in the American southwest. Both the RS 7 and RS 6 will use a more highly-tuned version of the new 4.0 TFSI that will boast 408 hp in the S6 and 518 hp in the S8. None of our sources or trusted other media have quoted a power figure for the RS-spec cars but we're guessing quattro GmbH will tune the RS 7 to match the S8 number at the very least.

Counter to the Quattroworld report, this new 4.0 TFSI is not borrowed from Bentley. Certainly association with such a luxurious marque won't hurt the engine's reputation any, but we've been positive that the new biturbo V8 always was an Audi-development since it was first confirmed to us back in 2008 by a board-level source at Audi. Bentley announced earlier this year that the 4.0 TFSI would be used in its Continental range of cars, no doubt as part of Crewe's own efficiency efforts and certainly to a Bentley tune... but the engine is Audi's and there's no question of that.

The Bentley fitted with the 4.0 TFSI is expected to debut at next month's Frankfurt IAA and we expect Audi to reveal at least one of its new 4.0 TFSI S-cars (S6, S7 or S8) at the German motor show as well. Each of the three are expected in the European market not long after and by next year here in the USA.

As for the RS 7, we've got multiple solid sources saying that it is in the cards for the USA. From a homologation perspective, that it shares engine architecture with the S7 and S6 due next year will make the RS 7 and likely even the RS 6 (sedan only) much easier business cases to prove.

Check out more photos, including a shot of the 4.0T FSI after the jump. And if you're the photographer, drop us a note to info(at)fourtitude.com. We have a few questions for you. Nice catch.

More Photos and Story at Quattroworld

More Spy Photos from the Spanish Test Mule Spied in May