When Audi introduced the new R8 Spyder model it said the car would only be available as a V10. Yup, the snarling 5.2-liter Lamborghini-sourced engine with 525-hp. Now, according to a report by Inside Line, the German automaker will offer a slightly more affordable version of the drop-top exotic, powered by the original R8’s 4.2-liter V8.

We thoroughly expect that once the new model arrives some time in 2011, it should receive a more powerful version of the 4.2-liter engine. In the R8 coupe and RS4, this high-revving V8 produced 420-hp, but Audi plans to deliver a 450-hp version of the same engine in the RS5 at the Geneva Auto Show next week.

We expect that the R8 Spyder 4.2 FSI will cost as much as $30,000 less than the current V10-powered model, making it slightly less exotic, but much more attractive to the Porsche Cabriolet crowd.