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.

4 thoughts on “Fan of the Cadillac STS-V intercooler heat exchanger

  1. I have added pusher fan, replacing top blower seals ect… I have viewed different pictures with a view of the laveno (doubt I spelled that right) tubes placed in with one I see both outer tubes w open end forward. The 2 centers open end towards back. Another shows open closed open closed. Can anyone tell me the proper way? And maybe explain why? By the way 2006 STS V 4.4 .

  2. I believe the coolant flow is through each of the 4 laminova tubes in series.

    An interesting ‘science project’ for the STS-V intercooler would be to replace the intercooler endcaps that direct coolant flow through one Laminova core after another with a custom endcap that directed coolant flow in parallel with all 4 Laminova cores and out after one pass.

    One expert mentions that it is helpful to ‘index’ the 4 Laminova cores, so that the large fins are facing the air flow.

    Laminova mentions that routing refrigerant from the A/C through the laminova tubes as cooling works well.

  3. Not to be a pain in the ass, but what happens if I don’t have the sequence correct? Will it run hot? Will it harm the engine? I was loosing coolant from the intercooler and had no leaks. That is when I decided the leak had to be in the blower. I was right one of the front rubber seals was bad. Looked to me to have been gotten into before. That is why I didn’t want to rely on how they were positioned and figured I would try to find out.

  4. I am not sure the tubes fit more than one way. Is that what you are asking?
    I believe they are cylinders will flow through them; which sequence the coolant flows to / through them is decided by the design of the header for them.

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