1967 400 Bird. Can someone tell me the correct way to install a new Manifold Heat Riser Flapper Coil Spring for Ram Air factory header or exhaust manifold, driver's side. I bought a new Manifold Heat Riser Flapper Coil Spring. It seems that no mater which way I put it on, it leave the flapper open. Seems to me when cold, the flapper should be closed when the temperature is at 50 degrees for a newly installed coil??

Also, for the coil stud, should there be a "C clip" or retainer on the end where the split stud has a indented collar?

As always, any help is appreciated.

Can you pre-load the spring? Try turning it at least one turn in the closed direction? I have never even seen one that wasn't rusted solid.

What he said. It needs pre-loaded to close the baffle. At room temp, it should be closed and the spring is what does it.

Thank you for the response, much appreciated. Yes I can. Now I think my problem is that it appears I need a stud from the head to the ram air exhaust manifold as I can't see how a bolt goes in other than pre-mount the stud and then put on a nut, but I can't find anything about a stud for the ram air exhaust to head. If you happen to know, please reach out. Thanks.

Rus,

Thanks for confirming. If you can help with the head to exhaust stud v bolt question posted above, that would be appreciated as well.

Can you use an Allen head cap screw? I fought header bolts getting loose and blowing gaskets years ago. Finally drilled Allen head cap screws and lock wired them down. It took some work, but they did not move ever again.