Thanks for responses... the fenton will bolt to a newer intake manifold.. not a 216 specific unit
There is no provision in the fenton casting to install a heat riser flapper - its not a missing piece, it was never designed with one in place.
I also am leaning towards a modified original ( I already have a set) though that would involve changing some exhaust piping... probably better to do it right the first time.
I am changing from a set of dual carbs on a fenton intake as I don't like the drivability for around town and lower speed cruising... it seems to run fine on top end, and out on the road but low speed operation and putting around in high gear isn't as "user friendly"
anyone have one of these older heat riser fentons on a running motor?