348 hi-horse exhaust manifolds

[bubbletop61]

I have a terrific pair of "new to me" hi-horse exhaust manifolds. The condition is EXCELLENT, with the exception that the heat riser tube ends at the top of the manifold and does not protrude.

I have never seen one of these tubes and how it supposed to run from the manifold. Was this tube connected to the thermal choke on the center 2GC? There must have been a coupling of some sort between the manifold and the carb? Was there a flex hose anywhere in the system?

Any leads as to where I could see a picture of a "correct" installation?

Thanks Guys
BBTP61

[bubbletop61]

Has anyone every had any success in replacing the tube that runs through the right hand manifold? How did you do it?

[roaminchariot]

On my manifold, the tube inside is separate from the one outside. You slide the outside tube into the one already in the manifold and then screw it onto the bi-metal auto choke on the other end. I bought the heat riser tube pre-bent from Late Great Chevy, I believe. It works well.

[348NUT]

As far as I know the tube should not protrude. I think your manifold and tube are fine. The tube that runs to the carb slips into the one in the intake as Roaminchariot said. Good luck. NUT

[bubbletop61]

Thanks guys for the responses. Now, all that said, has anyone gone the electric choke conversion route. What comments do you have on this?

I have also seen a couple of different configurations of the housing cover for bi-metal type choke set up. One cover is die cast like the carb body and has the neck for attaching the tube
sticking out perpendidcular to the cover. I have seen another that has the threaded neck coming out pointing toward the front of the car, and appears to be molded. Which one is correct for '61?
Thanks,
BBTP61

[roaminchariot]

Mine has the threaded fitting perpendicular out the side and it lines up with the manifold tube I purchased for it. Not positive if its correct, but I believe it is.

[fatride]

I replaced the hot air choke on my 60 Impala 348 three duce. Rates up there with the electronic ignition, disc brakes and overdrive tranny. Not for the restorer but a big improvement over the stock choke.:cheers

[SS425HP]

Ray, I'll ditto that. Electric choke works very well. Much better than the hot air. And, the wire can be hidden. I have never had any one complain about the choke not being correct. Of course, I don't go to these high fallutin judged shows, either.

Fred

[bobs409]

Where did you guys get your electric chokes? My 409 doesn't need a choke even in 20 degree weather but my 283 could use one. It has the Rochester 2bbl that has the same choke housing setup.

[fatride]

http://www.hotrodcarbs.com/