Audi is believed to be testing a mule for a mighty RS3 model. Auto spies say evidence of this could be the older model's 2.5 liter five cylinder turbocharged mill and not an inline-four.

If they are testing a 2.5 liter five cylinder turbo engine for the RS3, it could produce an extra 20hp and 15Nm of torque for a total of 355hp and 465Nm. Perhaps enough to compete against the A45 AMG.

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