1940 carb with headers

Invectivus

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I have a 1940, which has the choke tube running off the manifold, and I have a tube header I want to put on. I assume that (if I want to keep my 1940, which I do) I can't get away without having to drill a hole for that choke tube in one of the header tubes, and adding some mass at the mount point to tap? Also, as the stock manifold has pressure build up from all 6 cylinders, will the performance of my carb/choke degrade due to being fed my only one cylinder? should I fab up a spider to feed from all 6? That would seem a little excessive, just asking though.
 
Howdy Invictus:

The heat tube is just pasing heated air up to the bi-metal coil spring in the choke housing. The tap of the OEM exhaust manifold goes completely through. it draws air from the bottom, heats it and is drawn by vacuum into the choke housing. A simple way to adapt a hot air source from a header is to wrap a coil of copper tubing around a header pipe, close to the head and route it up to the choke. It it is too loose it may rattle (Don't ask me how I know). I wrapped the copper tube to the header with some header wrap material and secured it with machinist wire. It worked as good or maybe a little better than OEM. PS- don't touch the bare copper tubing. It will be hot.

I'm curious. How much choke do you neet in San Jose?

Adios, David
 
I don't know quite yet how much choke it needs, I just got her 'running' a couple months ago, though that's just the engine. I put a known good C-4 in with it for expediancy (original 3 speed manual car) and still need to route the cooling lines, replace the throttle linkage, install the power booster/MC, route new steel brake lines to the flex hoses, and replace the u-joints. Then I can install the header and get to the muffler shop to get new pipe and a muffler. before i really drive, I want to replace all the rubber up front and the ball joints, and get new shocks. When i bought my mustang, it had been sitting since '90, and pretty much everything needs to be worked on.
 
yup just like david said... except all I did was run the tube from down low through the middle of the back 3 pipes (where all 3 meet) and clamped it to # 4. I'm using the extra long choke tube from CI. basically it's where it should be the hottest, pulling cool air to heat it up as it goes through the hot area.

oh and I'll add, don't drill any hole in the header :nono:

sounds like a great resto plan. did you rebuild the engine with any other goodies?
 
I had a list of grand ideas for the engine rebuild but when I tore it down, the block had a lot of rust (left outside for a couple years). I had the block hot tanked and overbored (had to go 60 over) and right as I was getting ready to start sourcing parts I realized that wasn't what I wanted to work on at that point. Coincidentally, someone advertised their 200/C4 on CL for $300 (in car) so i drove it, liked it, bought it, and installed it.

Right about then I bought my 64 falcon convertible, and changed where I wanted to pour my creativity. Also, She Who Must Be Obeyed (if i can channel Kastang for a moment) looks unfavorably on a yard of cars, so when I get the mustang going I'll hopefully find someone to give it a new home. My torn up 200 will probably get tossed into the falcon when I start working on her, though my eventual plan is a crossflow EFI, unless Mike gathers up an efi kit for the aluminum head and offeres the bungs predrilled.

And thank you both for the idea, that's exactly what I'll do. I didn't care for having to drill into my headers, and i'm relieved that the carb draws through air rather than needing positive pressure from the exhaust. It's really temperate in california, and other than jumping the mountain to the beach, there isn't much elevation change either, so i don't think i'll have nearly the issues with tuning some of you fellows have.
 
:) It should`nt be too difficult to build a heat stove to put one end of your heat tube in to get hot air to your choke.That way no drilling of header tube.
You should be able to clamp it to one of the header tubes with a stainless hose clamp or two.
Leo
 
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