How important is the rings that seal the intake manifold to the head? I have a late 235 and am using a early 235 intake/exhaust and the rings would not fit in the block so I left them out. Now the engine does do run unless 80% choke is used and backfires thru the carb once the choke is pushed in. ????leaking intake manifold??? Do I need a late 235 intake and rings for a correct fit???
