Lowering IAT For A LS Motor Swap
06-07-2015, 09:54 PM
#1
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Lowering IAT For A LS Motor Swap
I did the LS1 swap 6 or 7 years ago, and like most people ended up using a 90 degree intake bend between the throttle body and MAF sensor. Stuck an air filter on and called it good.
When I had the engine tuned at Slowhawk last October we drove the car around for a while to gather data after some adjustments. We saw that the IAT was up between 170 - 180 degrees and that has the effect of the ECU dialing back power.
I didn't want to do any radical mods to the radiator support or hood, so I came up with the idea of boxing in the air filter and running a hose down to draw air from under the radiator. I don't know if anyone else has tried this approach - I haven't done a search on the topic.
I bought a scan tool and tested the 'prototype' phase of the box this weekend. No insulation and a 3" dryer hose not carefully placed to avoid radiator heat. I wanted to see if I was going to get enough improvement to bother refining the box.
Much to my surprise the IAT was steady at 120 degrees while driving. A 50 - 60 degree drop is pretty good for the first test.
The next step is to put reflective insulation around the outside of the box and route a tube so that it is off to the side of the radiator. No mods needed in the engine bay.
Some pics:
Not the most elegant looking thing but it will at least be shiny with the insulation. It looks like the hood won't close in the pic but the highest edge is about even with the radiator support and the lower edge is a little below the fender line.
Rick B.
When I had the engine tuned at Slowhawk last October we drove the car around for a while to gather data after some adjustments. We saw that the IAT was up between 170 - 180 degrees and that has the effect of the ECU dialing back power.
I didn't want to do any radical mods to the radiator support or hood, so I came up with the idea of boxing in the air filter and running a hose down to draw air from under the radiator. I don't know if anyone else has tried this approach - I haven't done a search on the topic.
I bought a scan tool and tested the 'prototype' phase of the box this weekend. No insulation and a 3" dryer hose not carefully placed to avoid radiator heat. I wanted to see if I was going to get enough improvement to bother refining the box.
Much to my surprise the IAT was steady at 120 degrees while driving. A 50 - 60 degree drop is pretty good for the first test.
The next step is to put reflective insulation around the outside of the box and route a tube so that it is off to the side of the radiator. No mods needed in the engine bay.
Some pics:
Not the most elegant looking thing but it will at least be shiny with the insulation. It looks like the hood won't close in the pic but the highest edge is about even with the radiator support and the lower edge is a little below the fender line.
Rick B.
06-09-2015, 06:45 PM
#3
Race Director
I have been wanting to do something about getting colder air to the engine. As long as I am moving air temps are okay. If I get into traffic I can see temps climb like you describe. The cooler air has to help. I have a box full of fittings and connectors. I was never able to get where I could get cool air. I even thought about going through the side of the radiator support.
Nice work Rick.
Nice work Rick.
06-14-2015, 04:12 PM
#4
Melting Slicks
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If you could get that box made out of ABS or carbon fiber, it would not only look great but help tremendously with heat soak as well!
08-03-2015, 10:43 PM
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When I tried to fit the box with a nicer intake hose (i.e. not a dryer vent hose from Lowes) I found there wasn't enough clearance to bend the hose with the spreader bar in place. I have the DeWitt's replacement for the stock small-block aluminum radiator that has a nice blank filler plate on the passenger side of the support.
I cut a hole through the support and after some trial and error found a good place to mount the air box in the nose in front of the radiator.
The first day out was in the low-mid 90's and intake temps were running 95-96.8 degrees while moving and 106 degrees while stuck in traffic. I'm still playing with the Torque app to graph the intake air temp vs. speed but I'm very happy with the reduction in temp. I can imagine the temps would have been well over 180 degrees if the air filter was still inside the engine bay.
Rick B.
I cut a hole through the support and after some trial and error found a good place to mount the air box in the nose in front of the radiator.
The first day out was in the low-mid 90's and intake temps were running 95-96.8 degrees while moving and 106 degrees while stuck in traffic. I'm still playing with the Torque app to graph the intake air temp vs. speed but I'm very happy with the reduction in temp. I can imagine the temps would have been well over 180 degrees if the air filter was still inside the engine bay.
Rick B.
