Choke Tube Installation Advice on '62 327/300

[Claude Edwards]

Getting ready to install the choke tube setup that goes through the manifold and connects to the AFB carb choke on the top side and loops underneath the manifold and goes up to the vacuum connection on carb.

• Any advice on installing this setup? Since it goes up to a vaccum connection does it stay vacumm tight going through the manifold?
• I have noticed on some pic's an insulation type cover on the tube going from the manifold and the choke input, I have not seen anything of this nature in the AIM about an insulation cover of any kind, is this necessary for protection from the heat from the manifold?
• Concerning the tube going through the manifold does the top and bottom tube mate into it or does it slide in the manifold next to the inside manifold piece and hold tight by itself. I know the bottom tube has a hold down bracket that holds the tube setup in place but does it just slide up in the manifold and seat itself?
• Does the tube portion that goes into the manifold install best from the top or the bottom of the manifold?
• Should the connections on the top and bottom of the manifold be sealed in any manner once installed? Thanks for any input.

 

[critchie]

There's 3 tubes. 1 on top of the manifold to the carb. 1 inside the manifold. 1 underneath the manifold that held in place by that bracket to which you refer. Look at catalogs from the usual Corvette parts suppliers and see if they have parts blowups of this.

I believe the vacuum connections stay tight because these are all interference fits.

I always wondered about that insulation type covering too. Sometimes you see it. Sometimes you don't. When I bought mine for my '62 from Paragon. it did not come with the insulation.

I believe you'll either need or want to take the manifold off the car in order to get the tube that's inside the manifold. Good luck with that. You can get to the middle part of the tube from the inside of the manifold. Probably require some careful drilling from above and below to get the ends. And ripping outthe middle from inside.

Then all 3 tubes are interference fits. When the middle one goes in, it'll leave room for the top and bottom ones to go next to it.

I wouldn't bother to seal the tubes where they go into the manifold. Permatex does make exhaust system sealer. But it'll look terrible if excess spills out.

This choke circuit isn't a real strong vacuum. It's something less than manifold vacuum. All you're trying to do is keep unfiltered air out of the choke.

 

[Claude Edwards]

Thanks Critchie I am out of town reading the post and plan on tackling this when I get back. I appreciate your input as I had not been able to find any info on how they were put in place. Thanks for helping.