Then again you can look at it from a different direction, the trick is not the amount of cooling the trick is the insulation of the water tank, that way it can take hours if it wants to cool, although having a business that does refrigeration and aircon is also a wee advantage.
It is not possible for the charging system to run the peltiers to give a real time effect, so the only other way is to use ethyl glycol as the "storage" chill down 3 liters of liquid to about -18 then when ready, pump that through the intercooler this will give about 20 seconds of super cooling, the trick will be to work out the min temp possible so as not to freeze the intercoolers with ice from condensation.

The other issue is that there is a 99% chance that after running up the peltiers to chill the tank that the battery is going to be dead flat, this will require a change over to another cell to run total loss ignition during this time with the charging system disconnected to reduce the load on the motor, pumps and ignition can run off a 12 volt lithium battery for 1 min no problem, this helps to keep the weight down a little.