I had the Swanson $300. open air filter setup with nice billet aluminum MAF adapter and anodized aluminum brackets and air diverter. Very nice quality. I always wondered about the IAT though. So I did some datalogging yesterday and since I thought I knew what was going to happen I had ordered an Airaid system to replace it.

It was 83 degrees yesterday and today when I tested. I drove the exact same 40 mile round trip with a mix of in-town and rural 55-65 mph open roads.

Yesterday I had the Swanson 4" by 9" open K&N filter and their brackets and panels which supposedly block and divert hot fan air from the filter on the truck. Once going and up to temp the IAT1 temps (at the MAF) were at least 17-18 degrees above ambient. The IAT2 temps (after the intercooler) were between 25 and 30 degrees above that. So for a cruise on an 83 degree day the IAT1 temps were at about 100 degrees with the IAT2 temps between 125-130 degrees. This was the best case while at a steady cruise of at least 55 mph and no stop lights. Swanson told me they stay within 10 degrees of ambient.

When you got into traffic the temps rose quickly. Averaged 30-40 degrees above ambient with the below 45 mph heavy traffic and occasional red lights. Saw a high of 130 degrees (47 degrees above ambient!) sitting at a couple of lights. The IAT's stayed about 25-30 above this which put them over 150 degrees at points, and we're not under any boost yet. What surprised me the most was that the IAT1 temps took so long to drop even when moving in traffic. I mean literally miles to get 4-6 degrees of drop. I had to run at 55 mph without stopping for about 10 miles to get them back to 17 to 20 degrees above ambient again.

Today I installed the Airaid. I've heard good and bad, but figured it had the exact same filter as the Swanson and was basically enclosed, drawing air through the (probably) too small factory hole in the fenderwell. I am planning on adding a fresh air hose to the box for additional cool air, but decided to go ahead and try it just to see if there was a difference.

Same exact route and same temp today so it was a very even comparison. On the open road section my IAT1 temps were within 3-4 degrees of ambient for an improvement of 13-14 degrees. The IAT2 temps were the same 25-30 degrees higher, but of course were lower than the open filter due to the IAT1 temps being so much lower.

In town traffic and stop lights saw the same temp rise as before, but never exceeded 22 degrees over ambient, versus up to 47 degrees over with the open filter. Most of the time they remained 12-15 degrees over ambient. But the biggest difference was in how fast the temps dropped when you pulled away from the light. Before it took miles (literally) to see a 6 degree drop in temps at the IAT1. With the enclosed unit they dropped 10 degrees within a 1/4 mile tops, and dropped the rest of the way to 3-4 above ambient within 1/2 to 3/4 of a mile. HUGE difference as the IAT2 temps are so much improved due to the lowered IAT1 temps.

It's basically like jumping on your truck on a 65 degree day versus jumping on it on a 85-90 degree day. There's (on my truck) a 20-25 degree reduction on the in-town slower speed stuff and 14-15 degree reduction out on the open road.

Sorry for the length, but I figured somebody might be interested in my results.

Jody

 

Great data!!! Thanks for sharing...... Joel

 

Great post! I've got the K&N FIPK and have wondered the same thing about the temps. I've used a little more crude method and installed a wireless thermometer right next to the filter. I've experienced pretty close to the same temp differentials. What equipment did you use and where do get it to hook into the onboard sensors?

 

I started out using the datalogger on my Predator, and then swapped over to CarCode, a datalogging program for my laptop. You can read everything with these, pretty cool. In real time also, as you're driving.

They both hook through the aldl port under the dash.

Jody

 

Great Post

I have been doing the same thing with my Predator. I always find my self plugging it in and checking temps out.

I have the Fast Air by PSP. While cruising my IAT-1 is normally 1 degree cooler than what my overhead temp gauge reads. When I pull up to a light the temp slowly begins to rise, and if I sit there long enough it will get anywhere between 15-25 (depends on outside temp) degrees above outside temperature.

Once I start to move the IAT1 starts to drop, and if I start moving fast enough it will quickly drop to where it was.

I data logged a little today. It was 97 degrees during rush hour. Didnt get above 30 and 85% of the time I was stopped. This condition seemed to stress the CAI, and my temps were up and down, but really never dropped below 99.

 

In addition to how much lower the temps were in an enclosed system versus the open one, the other biggest difference was how rapidly they drop when you start moving again. With the open element air cleaner it takes a LOT of driving to get any significant reduction in air temp, miles in my case.

Jody

 

Apologize? You must be kidding! And yes, there are many interested in your results. Science talks, BS walks.

This is excellent data! Mind if I steal it for my Web site?

 

Not at all Tim, I appreciate it actually. I know you're very knowledgeable about these things, and I've only been playing with the Lightnings for a year. I kept reading about the different CAI's and just wanted to know the truth (at least in my case).

Jody

 

Great data,
My IAT 2 temp stay around 250????
I have a fluidyne exchanger and am running 14psi.
does this sound normal??
Stock eaton
Vince

 

That's about right. It was about 80 degrees here in Houston last week. My intake temps were running about 104 degrees on the highway and 114 degrees in traffic.

I bought the Hellion from Outrageous Performace. It's been a lifesaver!

 

Are you sure they're 250 degrees?!! If true, I'd guess your intercooler pump is not working.

No, that is not normal at all. You need to check that out immediately.


Jody

 

The other thing to come out of this is I found that the IAT2 (after intercooler) temp will immediately rise as soon as you lift off the throttle. Even if you're going 65 miles per hour, which takes airflow through the heat exchanger out of the picture. Makes me believe the pump speed is regulated relative to TPS or load, and speeds up when those items change upwards.

As soon as you start to accelerate it immediately starts to drop a few degrees, so I guess it's not a big deal. I was just wondering if it can be changed to run at full power, or "hop it up" so to speak through tuning.

Jody

 

I've done a very similar thing but with a seperate temp sensor.

Stock air box and snorkle was almost always within 1 degree of ambient.

An open filter was just like camcojb says his did.

I made a simple splash shield to prevent fan wash. It faired actually well. It supprised me! The temps were significantly lower but it had the same low speed problem of getting very hot.

Now I've made a set up almost identical to big6 (or whatever he goes by). It runs 1 degree above ambient and yet the top is open. So it still will get hot in slow traffic (crawling) but nowhere nearly as quick. And it'll cool off in about 10 seconds due to the underbumper scoop.

My next try will be closing off the top, sealing off the end-to-fender opening, and stepping my 4" drainage pipe down to a 2.5" so I can turn right again.


Rich

 

Yep Rich, I'm sold on the completely enclosed system for these trucks. The more so the better. I'm going to add some extra venting to this box to allow better breathing. Then it should be real nice.

Jody

 

What "pump" are you refering to???? The intercooler pump doesn't change speed. Is this what you ment?

As soon as you lift, there is very little air going through the engine - the throttle plates are closed. And unless you're into boost, the bypass valve is open - hence there is very little heat added from the supercharger itself.