ZDZ 40 #'S
My ZDZ 40 was turning a Mejzlik 20x10 at 7200, Menz S 20x10 at 6100 and a Bolly 21x8 at 7600 rpm , this was with a Bisson Pitts style muffer. I sold the engine with less than 2 gal through it because I was disappointed that the #'s were far below the Moki 2.1 it was replacing. It didn't seem to be the powerhouse that some have reported it to be. In my case the bison muffler may have been too restrictive but i wasn't about to start buying alternate exhaust systems to try to get more performance as that could be more costly than replacing with a more powerful engine.