Originally Posted by Dmgarage
I should re-phrase that. I installed it as it is now, but the rad came with the truck.
The surface difference between what you've got and what is needed is 36 percent. That's a lot; there are no tricks to overcome this it's just too big a number for fans and water wetter to overcome. I see the paint is probably custom and the opening in the truck's radiator support frame is probably too small so cutting that frame and touching up the paint is sure to be difficult, but I really don't see much in viable options.
However, over the years I done some tricky things where space in hot rods of the 1920's and 30's just didn't offer sufficient radiator space behind the grill without ruining the lines and or finishes. Some of these include:
- Installing a large as practical oil cooler with a thermostat. A lot of load can be taken off the radiator by cooling the oil. But the oil cooler installation needs to include a by-passing thermostat because you need to get the oil temp up but then maintain it. If it's too low the oil can't eliminate trapped water (a component of blow by) which reduces its and the engine's components life span. This can take 10-15 degrees off the coolant temp.
- Using hidden secondary cooling. Capture the coolant from the radiator before it goes back to the pump and run it through a looping length of 1-1/2 inch copper pipe clamped to the frame. You can have a well equipped plumbing or radiator shop roll a bead on the ends where the hoses will attach. Rubber hose adapters see WYSCO from your browser can adapt the 1-3/4 Chevy pump feed side hose to the 1-5/8ths of the tube/pipe. This adds volume capacity to the coolant and uses the contact point to the frame as a heat sink. This method keeps the thermostat and bypass intact and functional. You can tap a secondary radiator into the bypass but this leads into a remote thermostat housing which gets complicated and not very visually pleasing.