The phrase "full blast" means doing something at the highest or maximum level of power, intensity, or speed. It suggests giving your all or going all out.
Sentences with «full blast»
If you are in the car, stand them in front of the air conditioner on full blast until you can quickly get to ice and water. (kcregap.org)
When it is very wet, the heat only comes out at full blast when turned on, regardless of what the temperature is set to. (mechanics.stackexchange.com)