Given the size of the hole in the T stat is small to build a signifigant pressure the radiator would need to have a greater restriction, basicly need to be plugged solid or close to it.

If that were the case no cooling would be avialible from the radiator and a total overheat would occur with any signifigant driving.

Kevin

87 Turbo Intercooled Raider, roller cam, torsen rear diff, LSD front diff, lockup auto with modified converter, V6 brakes, low transfer case gears...