RussM05

Almost a year ago, I installed the Halltech CAI system. Very good looking carbon fiber filter box.

However, the Halltech air filter box is larger than stock to house the K&N filter. The radiator hose that normally clears the stock box must be moved over approximately an inch to clear the larger box and an insulation piece zip tied to the hose to help keep 200°+ heat from the box.

I guess I was not firm enough when I moved the radiator hose over and it was touching the air filter box. I did a scan on rural roads Sunday using HP Tuners and saw IAT between 111° and 127° or about 30-40° more than 78° ambient. Way more than they should be.

So, I removed the filter box, moved the radiator hose over more, then insulated the bottom of the filter box and hoses using the foam & foil tape from Home Depot designed for A/C ducts. Pretty ugly but I wanted to see if it made a difference before investing in a more elegant fix.

The temps now at cruise are 15°-20° above ambient but still a little more than I would like. If I set at a stop light, I was seeing a 50° rise. Obviously, heat soak from the lack of air coming thru the grill.

After studying the current design, its pretty clear that the radiator hoses placed so close to the air filter box is the problem. If they touch the filter box, it can get pretty hot in there. While I can't say with 100% certainty, this is not a fault of the Halltech design. Its simply the worst area to run 200°+ coolant lines.

Another area of concern is the air from behind the front fender into the air filter box. Out in the hot sun, the air can get pretty hot there especially on dark color cars.

I am playing around with some ideas to reduce the IATs even further. Stay tuned.

Kracka

Interesting findings, thank you! The AFE airbox keeps the coolant line in the stock position, but I'll have to look at mine to see if its touching or not.

leadville1

I ran cooler IAT's on my intercooled supercharged M3. That is horrible for a NA car.

Kracka

Right on, I got my turbocharged car within 10F of ambient.
(results below if anyone cares in looking at some random completely unrelated data)

RussM05

I took it all apart again and redid it. I insulated the front of the box facing the radiator, the bottom and the hoses. I took it out for a cruise while doing a scan and it did improve by about 5°. So now I'm seeing somewhere between 10 and 15° above ambient. However if you're sitting at a stoplight is still goes very high in the 120 degree range.

One strange thing I noted in HP tuners, I'm able to log ambient temperature as well as IAT. However the ambient temperature on HP tuners is about 5° higher than what is displayed on the dash.

Kracka

The coolant hose does rest on the AFE intake tube so I'm going to wrap that hose with something...maybe just a larger rubber hose slit to fit over it to act as a layer of insulation. It may be a losing battle though as that area is blasted with hot radiator air and radiant heat from the engine.

RussM05

I think you're right. That hose is too close to the housing and insulating it helps but it is not the final solution.

I have a idea that should be a game changer here. Stay tuned.

Higgs Boson

Do you need more horsepower at idle or something? They come back down when you move the car right?

There is no way around this. Don't race while idling and you'll be in good shape.

This is why there is an IAT vs ECT fueling modifier. Sometimes you aren't moving and sometimes you are.

RussM05

I don't know what I did to you, but you always are busting my *****.

As you may know, as IAT go up, air expands. Less Oxygen is a given volume of air, thus less fuel is injected to achieve the target A/F ratio, and as a result, and power takes a hit.

Yes, there are tables to adjust timing and A/F ratio but the fact is higher IAT has a direct inverse impact on power.

So the simple fact is, low IAT is what you want and ideally, as close to ambient as you can get. You preach lower temp makes more power.

When the IAT goes up sitting at a stop light, if you do a scan, it take a few minutes to go back down once you start moving. I have scans I can email you if you want to watch how long it takes to drop back down. It doesn't happen right away.

I observed when the radiator hose was in contact with the air filter box, the IAT were 30° to 40° above ambient. Way too much. After insulating the air filter box saw 10° to 15° increase. Not bad but the fact is the coolant radiator hose are way too close to the filter box.

Higgs Boson

the air cools immediately but the iat sensor gets heat soaked and doesn't report cooler temps.

I wasn't busting your *****,just being what I consider funny, and believe me, I'm hilarious,

dovervold

Spend all that money on carbon fiber, then have to wrap it in tin foil How about this. The hood vent is supposedly for down force. But I would guess that anything under 100 mph, the effect is minimal. If you remove the duct and let under the hood heat escape, I wonder what that would do for IAT's...

RussM05

I've been told that does help. But my thought is the radiator hoses are too close to the airbox, so if those are relocated more towards the center of the car, it should help.

dovervold

RussMO5, any chance you could remove the hood duct and see what your IAT's do with the vent open... Tks, Doug O.

dovervold

I am doing heads/cam/LT's so I can only guess this is going to add some extra heat under the hood. I asked ARH about coating the headers, and they said unless you are tracking the car don't worry about it. Heat is the enemy for sure!

jimman

Before you turn it into a space craft I would suggest this experiment. It will take five thermal couples and a meter to read temp. Place one under fender near intake, one in air flow stream at entrance to air box, one inside box to rear behind the filter (stagnate air), attach one to outside surface of air box near hose if you like and then the last one several inches from air box in free air under hood.

leadville1

I thought the Haltech was a double layer box that was insulated?

Try some header wrap on that hose, amazing how great that stuff works, you can actually touch pipes that have wrap on them, after they have been run hard.

Kracka

I am an advocate for ceramic coating exhaust components. I had my exhaust manifolds coated and even that made a difference. I know most won't agree with me, but I can't imagine running tubular headers without coating them first. To me, the only downside is cost, but worth it after seeing the difference. On a previous car I saw a 30F reduction in MAF temp by coating the exhaust manifold. That change was much larger than I'd expect on most setups though since it was turbocharged and the air filter drew air from the engine bay not far from the exhaust manifold.

eboggs_jkvl

I understand what you are working on and I think it is important to you to bring down the IATs, however...

Your picture of the insulation almost brings tears of sadness to my eyes. It reminds me of a space craft with all the insulation they add to do "stuff". Insulation might be an answer but it is just butt ugly!

Happy hunting in your quest to lower the IATs!




Elmer

dovervold

Tks for the feedback Kracka. Exactly what I was thinking. You put LT's to add some power, then the extra heat robs some that HP. Who would you recommend for coating my ARH long tubes...

RussM05

I have a ARH mid-length headers that I had ceramic coated before I put them in. I am really surprised how little heat comes from them.

At this stage, I agree all the foil looks ugly but after reinstalling the hood vent duct you don't see most of it. You can't see the front of the air filter housing. This is just part of the development process.