I originally bought a Champion 3 row for my Regal and I ran it with a new clutch fan set up, the fit was great for the factory shroud but I had to buy larger radiator hoses.
This set up worked well in every condition except for when I got stuck in traffic at an underpass at the Dream Cruise with it being mid 90's and no air movement it climbed to almost 220 until I was able to get to a side street and move again where the temp dropped quickly.
So after that I decided I wanted full control of my cooling and went overkill and bought a 31" x 19" Griffen radiator with 2 rows with 1.25" tubes and then added the Intrepid dual fan set up and also put two 12" fans on my AC condenser, needless to say it never gets hot now.
Original install the Champion 3 row and the 307
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And the SBC with the Griffen and Intrepid fans
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