From some old time flight manuals.
P-51B (Merlin)
Emergency Take Off
Use oil dilution to obtain proper oil pressure at moderate power, and as soon as the engine will take the throttle, taxi out, and take off.
Warning
Apply throttle slowly but steadily. Sudden application of full throttle greatly affects torque.
Normal Take Off
Min Oil Temp 15°C
Max Oil Pres 90 lb/sq inch
Max Coolant Temp 60°C
C-54
Scramble Tale Off
Dilute engine and prop feathering oil in accordance with existing atmospheric conditions.
Check oil temperature rise. Temperature must rise at least 10°C above residual oil temperature prior to take off.
Spitfire V
Normal Take Off
Oil Press Normal 60/80 Minimum 45 lb/sq inch
Oil Temp Min 15°C
Coolant Min 60°C Max prior to commencing take off 100°C
Spitfire makes no mention of emergency take off. From the notes it implies when at readiness engines were kept warm.