Need help! Had a cracked block in my perfect running 216. Replaced the motor with a 1954 235 from a BelAir. The engine was professionally rebuilt. Engine runs great, but once its warmed up, at high rpm and load it sputters and hesitates. Drives me nuts. Timing checked, electronic ignition (6V). Runs great up to about 40-45 mph, then sputters. Vacuum advance? Distributor? Valve adjustment? All components have been rebuilt and/or replaced. Rebuilt single barrel Rochester, new fuel pump. I would love to be able to fully enjoy my truck again without swearing. Spent too much money to have it act this way. I do have a second distributor from the old motor that I could swap. Any suggestions? Shops don't understand fuel, spark, air without a computer. Need suggestions from old bolters. Thanks!
