'86 chevette heater core specs?

I am currently modeling a new waterblock design I have. Since the radiator is what take the heat out of the water I need to make sure the radiator can take the heat out of the water.
Does anyone know the W, BTU, or Calories per hour the '86 Chevette heater core is able to handle?

Look at the "Big Momma" that BillA profiled in this article. It is, for all intent and purpose, the same radiator (heater core).

Hoot