I'd get rid of that cover over the back of the radiator. It looks like it is blocking about 1/2 the air flow. As a test, take that and the fans off, and put on a factory fan. See what happens.
I agree.
Can you mount the electric fans without using that plate on the back of the radiator.
Try a mechanical fan with a low profile viscous clutch. Hayden now offers a muscle car low profile unit.
Troy’s cross ram Hemi 68 barracuda and it the same setup in his Hemi 68 dart. It’s got a 3 row high density core brass radiator. It’s a stock setup and fits correctly.
