Okay, I have always wondered how well my Twin Intercoolers (ATI) work. They have seemed to be pretty good after driving awile, but around town (or idling at the drags), the feel pretty useless.

So, I went to Kragen and purchased a couple of electronic temperature gauges that measure both inside and remote (end of wires).

I attached the outside sensor to the twin collector pipe in the engine bay, where I drape it with a heat reflective wrap. The other I attached to my latest invention, a 4 X 8 inch electrical Heat Sink that is bolted on top of my intake manifold directly underneath my SS hood scoop.

Results:

The intercooler temp gauge initially began to rise to about 110*, then upto 120* whilst puttering around town. The heat sink temp gauge rose towards 150* during town puttering. Air flow through the intercoolers and into the engine from the SS hood were minimal while in town.

I then took a pretty long drive to the coast. Both temperature gauges began to drop temps as soon as my speed increased above 40 for both gauges. I believe the gauges are somewhat stupid and slow to react, but nevertheless, the temps were reasonably accurate after attaining their end temps.

The Intercooler temp gauge eventually dropped to 69* and the heat sink dropped to 75*. Outside air was about 75 until I hit the coast, where it was about 65*.

My analysis:
1) The Intercoolers do work, but not below 40 MPH and they to bring the intake air temp down to a decent temp requires a significant amount of driving.
2) The Heat Sink and the SS hood scoop work. I am able to touch the heat sink immediately after a drive and it is cool to the touch..wait about 1 minute and the temp skyrockets as it is extracting heat from the manifold but is not being cooled by the airflow.
3) Empircally based information, showed to me that the intercooler temperature and the intake temperature were between 8 and 15 degrees apart most of the time, except when stopped and idling, when the intake temp difference was over 30 degrees.
4) I believe that the cooler air coming in from the intercoolers is also lowering the intake manifold temperature over time, as the two temperature gauges would tend to follow each other with a defined difference (10 degrees) between them.

My next steps are to measure the air temp coming into the MAF and the air temp leaving the S/C, then to measure the intercooler difference from the S/C.

I am curious how well a CAI system actually works, since its only advantage is outside air temp, not heat extracted air.

Since I could not use the 96 SS hood scoop for anything else after installing my S/C, I found a heat sink at a local electronics store and thought it might be of some benefit. I feel it works, but to translate that into any measurable power would be a guess at best.

UD

 

Nice experiment.

 

Thanks for the comment.

When testing I tried to remain smooth and mostly drove in cruise control at 65MPH where possible. The temps continued to drop, but seemed to flatten out when approaching outside air temperature. I assume it is impractical to expect anything lower than outside air temperature. When I started to hit some traffic, the temps rose again, then fell in unison, all the while at about 10* of difference. I did some pretty heated accelerations while all was quite cooled, the car ran great but the gauges barely moved afterwards. I think that was due to their slow response, not actual heat generated and measured.

When I am in town, I can definitely sense a power difference and sluggishness when the engine is hotter. I have a 180* thermo, but my fans are set for 188/192 versus stock settings.

I tried to analyze the air dam just below the intercoolers to see how effective they actually are. I think that when air hits the dam, it creates a high-pressure area that vents in all four directions (down, left, right, and up through the IC). High pressure is only attained when at significant air speed (i.e. 40 MPH) and then it flows through the fins, extracting heat. An IC can remain cool for a brief period, continuing to extract heat until it is equal to or hotter than the air mass. An IC is really nothing more than a heat sink with tubes. I've considered fabricating some air scoops for the ICs, but they would be pretty fragile if I hit a curb, whereas the air dams are flexible rubber.

UD

 

have you thought of mounting fans on top of the IC's to use at low speeds(traffic)? Definitely some interesting experiments you've got going.

 

Personally, I agree on some making some intercooler scoops. I think the flaps that come with the kit are not as effective at lower speeds.