Volvo Penta Aquamatic Duoprop vs Outboard 4-stroke Karel Overlaet, RIB Advocate Performance test comparing two Rupert R8s equipped with Volvo Penta V6 280hp vs Outboard 4-stroke 300hp. The test was executed on the Swedish west coast outside of Gothenburg on August 14th 2018. Others Also Read...Why an Electric Outboard Is Not the Better Choice NowSuzuki DF40A and DF40A ARI Without Licence in ItalyMercury Unleashes New V10 400R High-Performance Outboard A Hydrogen Outboard: Yamaha's Prototype