I didn't want to answer without checking first, but the manifolds we use have a 1.800 inch opening for both 235 and 261 (obviously since they are the same) so no worries on choking the flow with the manifold.
HOWEVER, the plastic carb riser that you get from the vendors is tapered and is 1.715 at the top and 1.690 at the bottom. Since the 235 gasket is 1.685, you are good to go on the 235 but the gasket that has the 4 slots is 1.780. So, my 261's use the 4 slot gasket so I am good there, but wonder if our black carb riser is a choking point on the 261? If so, any recommendations on how to make that hole bigger without ruining it?
Last edited by Deve; 07/22/2015 10:12 PM. Reason: last sentence
