Okay let me preface that this post is not about what radiator is better or why one is great and the other one is garbage. It will all be about facts and then you can make the decision of which one is best for you.
The stock radiator has an aluminum core with plastic ends that are crimped on. This particular stock radiator is a single core radiator that has 44 vertical rows from one side to the other. The core is 1" thick and the tubes are also 1" wide inside as shown below.
There are roughly 18 fins per inch as shown below.
The CSK radiator has an all metal construction of brass and copper. This particular one is a two row radiator that has 50 vertical rows from one side to the other. The core is 1.25" thick and each tube is .500" wide and are stacked as shown below.
There are roughly 16 fins per inch as shown below.
Both radiators fit just like they should and have a 1.25" diameter inlet with a 1.5" bottom outlet. It is common knowledge that aluminum has a better thermal heat transfer than copper or brass, but that is a another story for another day. Once I installed my copper 2 core I have noticed that the temp gauge even with the OEM 195 degree thermostat holds the water temp just below 210 while the stock radiator held it exactly straight up at 210, although it could have been due to the age of the radiator. Hope this helps someone.