Audi's quattro team is hard at work on a hotter version of its latest compact SUV, the all-new Q3. Joining Audi in Switzerland last week for the international launch of the standard Q3, motoring.com.au had the (very brief) opportunity to try the yet-to-be-named go-fast SUV first hand. And we were quickly impressed by the TT-RS-powered model's straight-line urgency, rorty five-cylinder growl and muscular cross-drilled stoppers. The developmental (prototype) Q3 '228TFSI', as we've dubbed it, was debuted to international media by quattro GmbH technology boss, Stephan Reil at the media launch of the soon to be released Q3 compact crossover. Reil's team, the same masterminds behind the no-nonsense Q7 V12 TDI, shoehorned the five-pot mill deep into Q3's engine compartment after modifying the mounts, plumbing and wiring of ancillaries to accept the larger unit (note the under bonnet pic). Q3 228TFSI features a detuned version of the four-ringed brand's stonking five-cylinder, the same powerplant found in Audi's TT-RS coupe and RS3 hot hatch. In other applications this engine develops as much as 250kW/450Nm. In the hot Q3 this has been trimmed to 'just' 228kW, its torque figure still a closely guarded secret. When quizzed, quattro engineers grinned, saying only: "you vill find it to be 'adequate'". On test we found the five-cylinder car accelerated from rest to 100km/h on par with the 2.0-litre 155TFSI version driven earlier in the day, this is likely a result of the prototype model's cobbled together engine tune. With final calibration the output figures should see the hot Q3 model accelerate from 0-100km/h in less than six seconds. Top speed will be electronically limited (probably to 250km/h). What did come as a surprise, however, was the Q3's ability to race between corners -- the ferocity of the car's in-gear acceleration evidently sharper than its car's initial acceleration, and impressive by almost any comparison you could possibly draw. Stab the throttle in Sports mode from north of 5500rpm and the turbo hit brings forth an urgent surge in velocity. Mindful of the Suisse Polizei's excessive fines we reigned in our enthusiasm before drawing any unwanted attention. It wasn't easy though -- all the while you're being teased by a deeply sonorous and intoxicating offbeat five-cylinder burble that is keen to lure the right foot back to the firewall. As the car's suspension was yet to be fully setup for its altered ego, we didn't push our luck in the bends, instead jumping heavily on the upticked model's meaty cross-drilled (front) discs ahead of the curve. Here, the quattro's front-drive bias was still largely obvious, though this too is likely to be a result of the car's 'unfinished' state. Typical to the derivative model, the hotter Q3's steering was equally impressive, our only want for more weighting to suit the car's athletic aspirations. As a development model, the Q3 228TFSI is not yet a shoe in for production, and even if it does get the green light, numbers are likely to be limited. "This is just a temperature tester for us at the moment," Reil told press. "We needed some feedback on the idea, which is why I decided to bring it to the press [launch]. But the finished car will be very different: it will have adapted suspension and body parts, and so on. "So far the reaction to the car has been good, but we have to make the business case before going much further. Right now it's a fun idea, but those don't always turn into real production cars." Timing, pricing and full specifications will be announced if and when the model is released.