Air box question for ls swap
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Joined: Sep 2012
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From: Tucson, AZ
Air box question for ls swap This may not be the right section, but here goes. I am getting ready to build an airbox for my 65 nova ls swap project. I will be building it out of 1/8 abs and cutting a hole in the radiator support to supply clean air.
Something like this: https://www.stevesnovasite.com/threa...ke-box.603825/
My question is about the top. It seems most people leave the top open or try to seal it against the hood. This seems like it would pull in hot air from the engine compartment unless it was perfect. I almost never see anyone use a flat lid. Is there a reason for this? With a sealed lid, the intake would only get clean air. Maybe I am missing something....
Anyone have any ideas?
Something like this: https://www.stevesnovasite.com/threa...ke-box.603825/
My question is about the top. It seems most people leave the top open or try to seal it against the hood. This seems like it would pull in hot air from the engine compartment unless it was perfect. I almost never see anyone use a flat lid. Is there a reason for this? With a sealed lid, the intake would only get clean air. Maybe I am missing something....
Anyone have any ideas?
When I built an air box for the previous motor in my car -- I took a similar approach to the pics the OP linked above. I built it to within about 1/4" of the bottom of the hood. Then I picked up some window insulating foam from Home Depot/Lowes, put a slit in the foam and used 2-sided tape to attach it to the top of the box. When the hood closed, it compressed the foam creating a seal for the top of the box. Just a thought....
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I think you have it right. To have a lid top instead of attempting to seal against the hood, would do a better job of keeping hot underhood air from leaking in. And in some cases I think the large square filters like in the factory boxes are probably more flow-efficient than some of the conical ones (more surface area). Late model GM boxes have inlets pulling cold air from the fender already.
On my truck, I left the stock box, used a high flow filter, and only replaced the elbow from the box to the throttle body with an Airaid elbow. And the only reason I swapped that, was mostly because the resonator portion routed under the manifold beauty cover, which seemed like it could pick up some heat. Now it's a straight shot.
On my truck, I left the stock box, used a high flow filter, and only replaced the elbow from the box to the throttle body with an Airaid elbow. And the only reason I swapped that, was mostly because the resonator portion routed under the manifold beauty cover, which seemed like it could pick up some heat. Now it's a straight shot.
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From: Central Cal.
I think you have it right. To have a lid top instead of attempting to seal against the hood, would do a better job of keeping hot underhood air from leaking in. And in some cases I think the large square filters like in the factory boxes are probably more flow-efficient than some of the conical ones (more surface area). Late model GM boxes have inlets pulling cold air from the fender already.
On my truck, I left the stock box, used a high flow filter, and only replaced the elbow from the box to the throttle body with an Airaid elbow. And the only reason I swapped that, was mostly because the resonator portion routed under the manifold beauty cover, which seemed like it could pick up some heat. Now it's a straight shot.
On my truck, I left the stock box, used a high flow filter, and only replaced the elbow from the box to the throttle body with an Airaid elbow. And the only reason I swapped that, was mostly because the resonator portion routed under the manifold beauty cover, which seemed like it could pick up some heat. Now it's a straight shot.
