The DA 100 is just over 11.5" cap to cap--I KNOW there are narrower engines out there than that! The Brison 6.4 twin looks pretty narrow--only 9.75" without the plugs (which are angled). Is there anything out there narrower? I've got a 100" Corsair cowl to stuff the engine into and the inside diameter of the cowl is 11-1/8" and I don't want to have any holes for spark plug caps in it.