Have not personally run a 4-barrel on a 235, but I have run 400 CFM Carters on a 121 CID 4-cylinder Pinto, a 195 CID 4-cylinder Pontiac, and a 300 CID 6-cylinder. Since the Carter AFB is an airvalve carb, it was not too much for any of the above (granted that the Pinto 121 was a race engine).
All of these installations worked very well. The 300 CID 6 was in place for more than 400,000 miles and was untouched during that period. It was mounted sideways, and delivered 22 plus MPG at 70 MPH in a van.
The secret can be in the tuning.
Jon.
