The LMC catalog tells me that the 6 cyl. and 8 cyl. radiators are all the same, with 3 cores plus a trans. cooler. A properly working stock radiator with proper shrouding ought to be OK. When I put a 383 TPI engine in my '62, my goal was to be able to drive the thing in traffic in downtown Chicago on a 100 deg. day with no worries. My point is, you have to think about the driving you will be doing and then make sure the cooling system matches, with the asumption that you may have A/c in the future.
