Yep, it is a 4 stroke. It can be converted to run horizontal with the correct parts and some aluminum welding (for the oil filler/sump) but the question in the end is it really worth it? I started out working in my uncle's lawn mower shop when I was 9. I am now 52 and those years still rate up high on my list of best. Personally I wouldn't spend the time and effort to convert it but then I am not you so I'll stop right here and wish you good luck in your endeavor.