Larrowe & Sons makes/made an adapter ring for between the 216 intake the later 235 head (and vice-versa, I'd guess) with larger ports.

Their on-line catalog does not work.

Here is an adapter ring in a photo by Pre '68 Dave. Maybe he knows who sells them?


Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.