Do all 67-69 small block Barracuda's run hot? Rant

What is the antifreeze concentration? 50/50 is a good all around mixture. But if you increase the amount of antifreeze in the ratio, say to 70/30, you reduce the coolant's ability to shed heat. If all else fails, try a 30/70 mixture….30% antifreeze, 70% water.
Not sure exactly on the mix other than it is not 50/50. Probably more like 70/30. One more thing to look at. Thanks.