Volvo Penta Aquamatic Duoprop vs Outboard 4-stroke December 13, 2021February 4, 2023 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...John Moxham Internationally Renowned Naval Architect and Ultimate BoatsRIBCRAFT Steps Taken to Reduce Carbon FootprintMercury Unleashes New V10 400R High-Performance Outboard World launch of Two New High-Performance Craft From Ultimate Boats