[bobcz100]

i just got this car and the cowl induction was never hooked up i got it hooked up with a valve in the vac line that is just a straight throw valve and the flap does work but when i shut it off the flap goes open is this wright or do i need a one way valve

[ranvette]

the flap should open with out the engine running

[ccpd166]

I have the same issue. If the cowl is to stay open when the eng. is off, what is the in-line vale for? It seems that is or should keep the cowl door closed when the eng. is not running for weather purposes???

[dscabra]

It is my understanding that the valve is a flow-restriction valve, which prevents the flapper from snapping open and closed. It instead allows the flapper to open and close more slowly.

The flapper is supposed to be open when there is a lack of vacuum, and will close when adequate vacuum is applied. So, as the butterflys open up under heavy throttle, vacuum is reduced and the flap will open.

Dave

[ccpd166]

Ok then that would explain the valve. I just ordered it so I will see if it makes a diff. But we are sure the cowl stays open when the eng. is off?

[dscabra]

Originally Posted by ccpd166

Ok then that would explain the valve. I just ordered it so I will see if it makes a diff. But we are sure the cowl stays open when the eng. is off?

Here is a great video of a TC'ers 70 El Camino on track (before he sold it ).
http://videos.streetfire.net/recentv...8f01445abc.htm
It should explain things. And yes, I'm absolutely positive that the flap is supposed to be open when the engine is off.

Dave

[ranvette]

there is no weather issue with the cowl open.The water drains right threw to the windshield cowl.The inner door is what gets the out side air into the air cleaner.To be honest the outside hood door could remain closed and the air cleaner would still get outside air threw the inner door.The outside door is more of a special effects thing.It is cool to say the least one of the best done ram air type systems of the time.Though I must say the mopar air grabber is a close tie with cowl Induction for coolest systems of the time !

[BlueSS454]

Originally Posted by ccpd166

Ok then that would explain the valve. I just ordered it so I will see if it makes a diff. But we are sure the cowl stays open when the eng. is off?

Yes.

[bobcz100]

thanks for the info i may order the other valve to slow the open and shut down thanks bob

[DZAUTO]

As mentioned, the inline valve is a flow restriction for MANIFOLD vacuum that is supplied to the vacuum pod which opens/closes the outer door.
This valve allows vacuum to flow freely in only ONE direction. The valve is installed so that the restriction is TOWARD the manifold vacuum source. To test the valve for proper installation in the vacuum hose, suck on each end of the valve. The end that has the greatest resistance to sucking goes toward the engine. Tooooooooooooo easy!
Under hard acceleration, this valve allows the door to open quickly, but is supposed to close it slowly. The ONLY thing that closes the outer door is manifold vacuum from the engine, thus, if the engine is not running, the door should NOT be closed!
The outer door is not so much functional, but is more for "show". The inner door, which is operated by an electric solenoid that is activated by a switch on the gas pedal, is the door that is really functional for allowing more air to the engine.
In the entire automotive world, particularly the performance world, there is almost nothing that matches the "magic" effect of the 70-72 CI hood.

[ccpd166]

Great thanks for the info. The valve is ordered ....
STeve

[LevonH]

The valve should have a black side and gold side. NORMALLY the black side is toward the engine. It is affectionately called the "oil" side and hence it is black..