I originally put a post like my original one here on roverlanders.com but I didn't get any responses so I assume they all have 2.25's. Yeah the 2.5 may be the best overall for parts availability and a little more hp just to help out the rover. I am still searching the net for ideas and options out there so we'll see how it goes. I will contact the guy above that has the adapters for the Mercedes conversion. thanks