I recently replaced the head gasket, flushed the coolant and checked for blocked cores, and replaced the thermostat. Unfortunately, my car (2003 Mitsu. Eclipse 4 cyl) still overheats, though not as much.
Last night i took the thermostat out and drilled a TINY hole in the housing to allow for the passage of more coolant. It still overheats. Would enlarging the hole help, or should I budge for the new water pump?
Also, could belt tension have any effect on the performance of these parts? I'd never replaced belts, and was unsure of the whole process...