70' Cowl induction flapper operation - Chevelle Tech
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post #1 of 5 (permalink) Old Oct 3rd, 11, 11:01 PM Thread Starter
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Rob
 
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70' Cowl induction flapper operation

I just finished my 70' SS with the factory cowl induction. The flapper closes when the engine fires and doesn't open again until you really put your foot into it, like WOT. Is this the way it's supposed to be or should it open easier than that? The vacuum solenoid is new and I'm pulling vacuum from the intake. The solenoid pulls the center of the flapper down in the center quite a bit as well. Has anyone come up with anything to prevent this?
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post #2 of 5 (permalink) Old Oct 3rd, 11, 11:21 PM
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Chevelle Doctor
 
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Re: 70' Cowl induction flapper operation

Are you using the check valve in the vacuum line to the cowl actuator? This is a metered restriction, and with it installed, the door is sluggish to open. If not, then check to make sure the vacuum hose is not being pinched by the hood at the sharp edge of the top of the firewall. THere is a notch in the hood that the hose and solenoid wire go into and are held there with a plastic strap like the one that goes on the inner fenderwell to hold the wiring loom in place.

As far as the pod pulling the flapper down, do you have any shims under the actuator pod? Mine does not and it sits flush all the way around when running.

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post #3 of 5 (permalink) Old Oct 3rd, 11, 11:22 PM
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Steve Johnson
 
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Re: 70' Cowl induction flapper operation

Sounds like it's working right to me. Vacuum is what closes the flap and WOT removes that vacuum and the flap opens. You do have to get into it pretty good for it to open all the way.
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post #4 of 5 (permalink) Old Oct 4th, 11, 12:57 PM
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Dave
 
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Re: 70' Cowl induction flapper operation

I would check those items Dave recommended. My Outer Cowl Door will open past half throttle, the inner flapper is operated per the switch on the gas pedal (can be adjusted some)

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post #5 of 5 (permalink) Old Oct 4th, 11, 4:37 PM
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Claude
 
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Re: 70' Cowl induction flapper operation

Quote:
Originally Posted by Steve Johnson View Post
Sounds like it's working right to me. Vacuum is what closes the flap and WOT removes that vacuum and the flap opens. You do have to get into it pretty good for it to open all the way.
X2!...exactly.

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