Chrysler made millions of cars back then that didn't have any trouble with cooling. Do you have a factory 7 blade fan and the correct water pump and is it a factory shroud? What is the engine tune like? Glen Ray uses cooling tubes which are similar to what big truck use, that is one reason they cost more. Bob is the best in the business.
AGREED 100%,
So what's the difference? The efficiency of the majority of today's replacement cores. They are not ALL created equal as the bean counters and "improved" manufacturing processes over the years have slowly degraded the efficiency in the chase of profit.
While discussing 1-2-3-4 rows there are several other variables, IE: tube thickness. the number of fins per inch, the thickness of those fins, louvered fins, staggering the rows, the methods used to manufacture the cores. All of these and a few more affect the efficiency.
