My point was that all of those builders thought they were safe, and none were.
Acid left in a cooling passage or exhaust cross-over will be a vacuum leak next year.
Do I understand correctly? Are you saying that this cast iron intake will develop a vacuum leak or a coolant leak if acid has not been completely washed away? I feel that the circulating antifreeze will certainly dilute any hint of acid remaining in the coolant passages. The intake air passages will have atomized fuel and are certainly too thick for any chance of acid eating through.
Perhaps I misunderstand you.
