In FCTM for B737-200 Boeing has a section for Overboosting
This is what it says !
Engine Overboost 7.18
A significant thrust overboost capability exists which could be used in emergency situations. This overboost capability should only be considered when ground contact is imminent.
Overboosting the engines when the situation is not sufficiently serious unnecessarily shortens engine life and increases the potential for engine failure.
In an emergency situation “firewallingthe thrust levers” should be considered.
This condition could result in an EGT or N1 exceedance.
Land at the nearest suitable airport