1 inch vs 1 1/4 tubing in rad

A large tube is equal to 2 smaler tubes,most rad builders will rate there radiator on horse power as far as it will cool up to a X amount of horse power,,,
you can have the best radiator in the world,,if the rest of the cooling system isnt as good,,the big dollar radiator dont meen squat,,,the distance of the fan placement related to the radiator can make or break how it cools in traffic,,
a fan shroud will help big time,,as well as a high running a decent water pump and thermostat,,and believe it or not the proper mixture of coolant,,50/50, by ading more anti freeze ,and less water,,or more water ,less anti freeze can alter how it cools,,i have been down this road,,i use a 4 row brass rad,,stock pump,cool flex fan blade 160 degree hi flow thermostat,currently no shroud and a blower motor runs 178 down the interstate,and usually less then 200 degrees in traffic,,
redoing the car,going to go with a large 2 row aluminum rad,hi-flow water pump made by evans cooling,and wil have a shroud build,,i hope it runs as cool,,as it doe currently