Air flow through hood scoop

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I removed my turkey pan and went with a K&N filter with the Xstream top. This is a 9" filter and top and it stands about one and a half inches tall. This is on a Holley 780 double pumper.

We arrived at this set up while tuning the carb on a chasis dyno this last fall.

There was virtually no difference in measurable HP or volumetric efficiency with the hood open or closed so I would imagine that this means that the ERA air scoop on my car is effective, is not constricting air flow, and is working well with the fans of the chasis dyno running. Now, obviously, sitting still it just allows air to enter the top of the engine bay.

You will notice that many photos of team cars did have air diffusers inside the scoop which appeared to be made from sheet aluminum with round air holes in them. There was too much air entering the engine bay causing the hoods to lift. Early cars had bonnet clamps added to them from the photo evidence I have seen.

The turkey pan on my car, once removed, did increase HP and torque, perhaps because we used a new gasket as the old one was not in great shape upon inspection. I think the turkey pan pays off when the engine AND ambient air temperature are really hot and you are running AT SPEED.

For normal running, with the turkey pan, what was happening was a bogging or lag in stop and go driving from stop or idle. My idle is low as I like the rumpa rumpa gurgle. Again, that lag could have been caused by what appeared to be an old gasket between the carb and pan.