Sealing the intercooler heat exchanger

[Bruce Nunnally]

I’ve been thinking about how to make my intercooler heat exchanger more effective before I add more parts.

The intercooler heat exchanger on the 2008 Cadillac STS-V is a small radiator in front of a line of other coolers and the main radiator – item 29 below.

Read More: http://caddyinfo.com/wordpress/?p=12067

[Texas Jim]

Did you ever get the retainers to fasten the belly pan back up tight??

[BodybyFisher]

After you seal up the air flow path, what about putting a pusher fan in the front?

Actually, I just did a search and I see you are considering a pusher fan

http://caddyinfo.com/wordpress/?tag=intercooler

[Bruce Nunnally]

There are two holes for retainers, one at the end of the foam seal to pin up the deflector. The holes in the deflector are round, and there are slots on the bottom of the radiator support. I was able to use some pushpin retainers turned side-ways to the slot length to hold the deflector in place. A bolt and nut would work well in terms of fastening, but there is no access to the top side of the slot, so the pushpin retainer allows a blind binding. So far they have held, so we'll see if they last. I went back and found some slightly larger pushpin retainers to try if these don't.

The intercooler cooling system works well except if the engine - supercharger - intercooler stack are all heat soaked; then the heat exchanger for the intercooler can't overcome the oven like heat load of the stack.

In my latest experiment -- while heatsoaked -- I tried spraying water on the intercooler heat exchanger or blowing air across the intercooler heat exchanger, but neither changed the IAT2 temperature in the manifold. This surprised me. I think what is happening however is that the heat load is so great that even lowering the water temp in the intercooler system slightly is not enough effect to change the heat loading in the manifold.

What others have done to address is replace the 24x14x1/2 radiator that acts as an intercooler heat exchanger with a different one, or add a second heat exchanger under the bumper.

The goal in either case should be to increase the cooling capacity of the overall system. I am not convinced that some of the swaps for the stock heat exchanger actually were improvements.

The OEM is a single-pass 24x14x1.5" radiator type heat exchanger. I am unsure of the fin density.

D3 uses a flexacool tube and fin type 6-pass exchanger with a 10" pusher fan attached to replace the OEM, and adds an additional bottle for coolant capacity.

A frequent V solution is to add the FrozenBoost or ZZP heat exchanger in series with the stock exchanger or the D3 exchanger.

Certainly adding a 2nd heat exchanger adds to the cooling capacity.

I am considering

option a: replace the oem heat exchanger with a Griffin dual pass radiator of a similar 24x14 size -- but x2 as thick

option b: add a front mounted heat exchanger similar to the ZZP or Frozen boost unit.

Also, my isolation of the cold air intake seems to be working -- I am within 5F ambient to IAT1 when driving. I am not sure what a good goal for IAT2 is. Right now I am holding at IAT2-IAT1=~30F steady state.

Obviously I would like for IAT2-IAT1 to be 0 but that's not realistic. 20F is probably the closest that is practical. There is very little actual information sharing on this topic because people are not careful to log a lot and give much context for the temps that they are seeing. [so in other words, the system may be working perfectly as intended and the 30F delta I am seeing was the goal]

I need to measure again without starting the engine on a cold engine bay cool morning -- at that point ambient, IAT1, and IAT2 should all be the same without the engine running, and I wonder if they are. I suspect that the sensor calibration is not all that perfect, and that my IAT1 reads +5F compared to ambient, and IAT2 +20F. I know on first turnon cold the IAT2 is already +20F. I can adjust those in HPTuners if that is the case.

It would be interesting to add actual temp monitors on the intercooler coolant, and flow monitors. However, the actual resulting IAT2 is the goal so logging / monitoring that seems fine.