Reply to "radiator deflector"

If your 'overheating' is occurring on the road at speeds over 25 mph, then yes, you need to direct all the air coming thru the grille to go through the radiator. If the problem occurs around town in stop & go traffic, you need bigger more powerful fans to shove more air through, and the lack of a deflector will hurt some. The vents on your hood do practically nothing to help either condition. But, what do you think defines "overheating?" Consider:
1)- Many Pantera engines (and other high performance brands) run just fine at 215-220.
2)- most Pantera water temp gauges lie unless calibrated in the car they will be used with.
3)- DeTomaso placed the water temp sender in the remote surge tank where it doesn't give a realistic engine temp. It needs to be in the block, under the thermostat where Ford engineers placed it.
IMHO, unless water spits out of the radiator cap while you're driving, or maybe when you park after a hard run, the car is NOT overheating. Rumbling and bumping under the car after you stop is usually a sign of low water in the system. Check the archives- this is THE most-discussed topic in Pantera-world since the '70s.