working with a 350 chev/omc setup, not omc cobra tho. i'm gonna run a closed loop cooling system. have everything to do it. had to get another set of center rise exhaust manifolds and risers tho, old ones shot. question; is there a difference between the closed and open cooling exhaust manifolds and risers? there is only one fitting on the manifolds, at the front. there are freeze plugs and screw in pug/caps in various spots. old manifolds are long gone, i don't recall how many port(s) there were. do i need a different set of risers and/or manifolds? or can i pull the plug from one of the ports, put a fitting in and go. thanks
