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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.
I know because I have mounted different sets coated and uncoated. Coated helps in several ways including cooler under the hood. I just another set of ARH's coated by Jet hot!
I bought intake tubes, MAF tube, and air filter to conduct an experiment. I located the air filter to the driver's side above the antilock brakes module and behind the radiator. I'm knew it would be hot there so this was just to determine for a fact how hot does it get.
As a reference, the Halltech saw 10-45 degrees over ambient but my experimental system saw 160 degrees or +80 degrees over ambient!!!!!!! That's how hot it gets under the hood.
I plan to reun the same test using the stock intake and other configuration. I believe a important key to power is low IATs.
I too am concerned about the higher ( in my opinion ) than what should be normal IAT Temps, from my experiences with my 2 G8 GT's with 6.0 L76 engines ( LS2 equivalent). Those will go back to within a couple degrees of Ambient rather quickly ( a minute or 2) when I am even moving slowly in town. On my new Z51 with a 160 deg T-stat, even at 80 mph for over 20 miles, they never go back down to that level. They really rise quickly when idling or stopped at traffic lights. In contrast, my ECT temps go back down very quickly, to the 165-171 range with my 160 deg. Lingenfelter T-stat.
Why am I concerned, IAT temps control timing, and if they are false or not, it still causes timing to be pulled. Now this certainly is no big deal if you are driving leisurely, but if you are having fun at the strip or heaven forbid... street racing, it is concerning.
What am I doing about it. Kracka recommended a DEI insulation kit for both of my radiator hoses, and I also picked up a DEI insulation kit for my CAI inlet pipe. Both came from Jegs. Together they totaled just under $100. Will install as soon as Halltech sends me their new CAI, which is on order. I also removed the radiator heat diverter and the reducing ring on the hood vent. That diverter only moves about 1/3 of the radiator heat away from the engine compartment. Hopefully more heat will be drawn out thru the hood with this removed.
I too am concerned about the higher ( in my opinion ) than what should be normal IAT Temps, from my experiences with my 2 G8 GT's with 6.0 L76 engines ( LS2 equivalent). Those will go back to within a couple degrees of Ambient rather quickly ( a minute or 2) when I am even moving slowly in town. On my new Z51 with a 160 deg T-stat, even at 80 mph for over 20 miles, they never go back down to that level. They really rise quickly when idling or stopped at traffic lights. In contrast, my ECT temps go back down very quickly, to the 165-171 range with my 160 deg. Lingenfelter T-stat.
Why am I concerned, IAT temps control timing, and if they are false or not, it still causes timing to be pulled. Now this certainly is no big deal if you are driving leisurely, but if you are having fun at the strip or heaven forbid... street racing, it is concerning.
What am I doing about it. Kracka recommended a DEI insulation kit for both of my radiator hoses, and I also picked up a DEI insulation kit for my CAI inlet pipe. Both came from Jegs. Together they totaled just under $100. Will install as soon as Halltech sends me their new CAI, which is on order. I also removed the radiator heat diverter and the reducing ring on the hood vent. That diverter only moves about 1/3 of the radiator heat away from the engine compartment. Hopefully more heat will be drawn out thru the hood with this removed.
Keep in mind that you now have multiple options for larger and more efficient radiators. The swap is relatively painless, and doesn't require much more than a a few bolts, a few clamps, and a flush.
Just another option if you want to give it a shot.
I put in the DeWitts radiator in my car and wrapped both radiator hoses in DEI wrap. I am going to Road America this weekend and we'll see how it does on a road course.
I know what my top speeds were before on the straights we'll see what temps/speeds look like this time. I also wrapped the exhaust by the tranny and differential. It is all about heat rejection for repeated results.
It also sounds like the cover on the intake manifold doesn't help with temp's either.
Reduction in ignition advance is secondarty to high IAT. The primary result of high IAT is lower density air, qhich means less oxygen reaching the cylinder, and less fuel needed to achieve the targeted A/F ratio. The net result is less power.
From my understanding, the ignition advance table are designed for optimal advance all things considered including IAT prevent pre-ignition.
I focus primarily on IAT reduction than ignition advance because if you solve the hight IAT problem the ignition advance will be optimized under the normal process.
It also sounds like the cover on the intake manifold doesn't help with temp's either.
I thought the same thing and left the thick felt like cover and plastic cosmetic cover that goes over that off when I swapped in a ported intake manifold.
Keep in mind that you now have multiple options for larger and more efficient radiators. The swap is relatively painless, and doesn't require much more than a a few bolts, a few clamps, and a flush.
Just another option if you want to give it a shot.
Agreed if you plan on frequently tracking the car at a road course. After being a passenger at Brainerd Raceway a couple years ago, and seeing another driver back his new Mustang into a tire barrier, I only dream of road racing. LOL Have to admit though, those rides were a highlight of that summer.
Still, it is worth first changing the T-stat.
For instance, all early Taurus SHO's had cooling issues if they pushed their EB engines at the strip or track. They needed bigger radiators. My EB Flex ( same exact engine) had NO issues. In fact when I was spraying 50-50 to 70-30 Methanol, I actually saw IAT Temps below ambient when dragging the car, with them finally going to maybe 4-5 deg above at the end of the 1/4 mi. Engine temps never exceeded 190 with a 170 deg T-stat. Eventually got several 12.9's @ 106-107 mph, with 60' times of 1.85 or less. Not bad for 3.5L and a 5,000 lb BRICK!
Test 2:
Stock air filter and intake tube. Removed baffle between radiator and hood.
Ambient temp 65° average.
Observed IAT +5° to 10° at 50-60 mph cruise over ambient.
Increases another 10° at lower speeds, stop & go under light throttle.
Here is a graph of the scan I did last night using HP Tuners and export to Excel feature.
The scan is 37 minutes long. The temp display on the infotainment screen showed 63-66° but for some unknown reason, the scan with ambient was +7° higher. Oh, well, but the real important thing is watching the IAT change.
Pretty interesting stuff. Love gathering the facts to support theory.
(Ceramic coated ARH mid-length headers and stock thermostat)
The red line is the IAT and the green line is the ambient and the dotted blue is the vehicle speed. Notice how the IAT starts to rise when the vehicle speed drops below 50 mph during the last 3rd of the scan and right at the end where speed was zero, it increase to 109°. No surprise, once up to temp, the slower you go, the more it goes up. Makes sense because less fresh air is moving thru the intake tube and heat soak
Right in the middle, when the speed dropped to zero, notice it increased again but dropped down pretty quickly.
First, its not a fair comparison to the first graph because I was really pushing it on the backroads of Central Texas. Look at the MPH changes as well at the ECT.
Second, look at the temp increase over ambient and the absolute IAT temps. It is higher than I would like for sure.
I've been fighting the radiator hoses being too close the Halltech air filter box. I am having trouble getting them away from the carbon fiber box. I've added insulation around the hoses and air filter box but the IAT are still higher than I would like.
I'm going to a fair comparison along the same route I took last night and try to match the speed.
First, its not a fair comparison to the first graph because I was really pushing it on the backroads of Central Texas. Look at the MPH changes as well at the ECT.
Second, look at the temp increase over ambient and the absolute IAT temps. It is higher than I would like for sure.
I've been fighting the radiator hoses being too close the Halltech air filter box. I am having trouble getting them away from the carbon fiber box. I've added insulation around the hoses and air filter box but the IAT are still higher than I would like.
I'm going to a fair comparison along the same route I took last night and try to match the speed.
If you’re looking for a way to get a handle on where the heat is coming from as it attacks your CAI, try this. Get this infrared thermometer.
I have an AFE CAI so I went to their website and made a copy of the different views of their CAI.
Then go out and make a run, come back in and leaving the car running, use the thermometer and check a bunch of different areas on the CAI and log them on the images you copied. You would be surprised to see where some of the heat is coming from that affects the CAI/ IATs. I’ll post copies of my log images when I get back home.
Here is a graph of the Halltech intake. Same cruise as the stock air intake.
Ambient last night was about 10° warmer than the previous night when I scanned the stock intake. Notice during the last half of the scan the IAT gradually increases and especially below 50 mph. The spread between the ambient and IAT is what I look at.
I've wrapped the radiator hoses in insulation and added insulation to the outside of the air filter box. Not pretty......
Just to understand how hot it gets behind the radiator, I had another test with just the air filter in the engine compartment right above the anti lock brake module. That one reported IAT of 160°.
I was at Road America this weekend and ran my new DeWitts radiator and the DEI wrap, temps stayed amazingly low my oil temp wouldn't even get up to 180 degrees while cruising and my water temp never went over 220 degrees.
With that said I was really questioning whether I was getting the full power out of the car. I noticed several LS cars at the track that wrapped their intake tube in Silver thermal tape. With a more efficient radiator you have to imagine more heat is getting dumped in the engine bay.
I am thinking of wrapping the tube and CAI cover in this stuff to keep a cooler intake charge. That intake tube on sits right where the radiator exhausts.
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.
I lol'd.
But isn't there some merit in trying to not heat soak your intake every time you stop? I would think not having to cool it back down every time you start moving is a better option.
But isn't there some merit in trying to not heat soak your intake every time you stop? I would think not having to cool it back down every time you start moving is a better option.
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.
Hi RussM05
I also am starting to investigate cooler air into the intake track. Have you removed the inner fender to see how the air intake is configured? is there a dedicated duct out to the grill? and is that little box behind the grille (right upper corner) the actual intake source that has only a1.5 inch hole in it? I was thinking of making a dedicated duct out to the grill if there isn't one.
I looked inside the fender and there is not much room there and it's not a dedicated tube to the front grill. Also, in the sun that area will heat up especially the darker colors.
02-27-2015, 02:43 AM
I know because I have mounted different sets coated and uncoated. Coated helps in several ways including cooler under the hood. I just another set of ARH's coated by Jet hot!
