Fan of the Cadillac STS-V intercooler heat exchanger

I have been thinking more about the STS-V intercooler heat exchanger design and replacement ideas.

Cadillac uses a separate cooling system for the Laminova style intercooler tubes, featuring a bosch intercooler pump and a 23.5″x14″x2″ outer measures intercooler radiator heat exchanger in front of the main radiator in the nose of the V.  So let’s call that a 20″ by 12″ working area.

The D3 solution is two-fold:  replace the heat exchanger with a tube and fin heat exchanger with 10″ pusher fan, and add a tank to hold additional intercooler coolant.

Other aftermarket solutions have included adding a new chin mounted heat exchanger instead of the current heat exchanger, or along with the current heat exchanger, or in series with a a tube and fin replacement.

After reading various experiments with adding fans on other vehicles, I am convinced that adding an intercooler heat exchanger fan is advantageous.  Although it is intuitive to think that a pusher fan could provide a block to the incoming airflow, testing has shown that is not the case on other models.

My plan is to keep the stock OEM heat exchanger, but add a 12″ pusher fan. I am thinking of a SPAL 12″/12v pusher fan or similar; space is a concern.  Use a fan controller to interface although it would be best if only on when the car is up to temperature etc.  The intercooler heat exchanger is in front of the main radiator, so pushing air through one will impact the other.

VA10-AP70/LL-61S * 12"C / 12V 12" Curved Blade High Performance Fan / 12V Pusher


Separately, I like the idea of using the LS9 coolant reservoir as additional coolant capacity especially in this system that is very capacity limited.