Tony Stark may need 10-cylinders in his R8 Spyder, but for most people eight-cylinders will do just fine, especially if it’s Audi’s burly 4.2-liter V8. After a year on the market, Audi will begin selling R8 Spyder’s with the “base” V8 engine to compliment the raucous 5.2-liter V10 engine. “Notably, Audi has liberated an extra 10 horsepower from the direct-injected 4.2-liter V8, so it's now rated at 430 hp. Peak torque holds ...

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