200 stock exhaust manifold hot air passage

[Frankenstang]

I'm finally finishing the 2in front to back conversion of the stock exhaust on my '66 (had it done halfway back...waiting for long back ordered 68-70 2in headpipe). At any rate, I noticed what appears to be steel or wire mesh in the bottom of the hot air choke tube passage going through the exhaust manifold to the 1100's choke tube. I also seem to recall having seen this before. The aftermarket 2in opening manifold I'm installing does not have anything in the passage...can anyone suggest a reasonable substitute for this material that will withstand exhaust punishment?

I think the purpose of this metal/steel mesh material (looks like a tiny, tiny birds' nest) was to be a half-arse filter for the passage to keep small debris or some such from being sucked up the choke tube (and possibly to further reduce vacuum bleed there)...since the choke heater tube appears to see a constant (albeit small) amount of vacuum even after the auto choke is fully open...but this may be wild speculation on my part as to its purpose...still would like to find a suitable 'exhaust' proof piece of mesh to semi (or very limitedly) obstruct/filter the passage...just not sure what type of material to go with?

Any thoughts (EDIT: like this is just crazy talk you're asking for something to break down and clog the port) or suggestions appreciated/welcomed. Thanks again in advance.

 

[MPGmustang]

sadly on my exhaust I don't have a wire mesh, its' just a straight through hole to the heater tube.

 

[bubba22349]

It’s suppose to have a tube straight through the manifold to the outside (air) than the choke stovepipe sides into it and the exhaust heats the air as it is drawn through. Don't remember any type of filter but suppose that you could have it on the underside below manifold. If you don't have a tube in the exhaust manifold then you could use one of the clamp on stovepipe kits.

 

[ludwig]

Somebody stuck that on there as a meth pipe mod. The stock installation is a tube stuck in a hollow recess in the manifold. The open end on the bottom of the manifold has a brass bushing around it; for what I don't know. The amount of unfiltered air through there is minimal compared to the immense amount of filtered air, such that it becomes negligible. However, when that hollow void between 3 and 4 burns through, you are sucking hot exhaust into the spring cap and it will 1) melt the cover and then 2) plug the little hole to the carb throat. Either one of these or both will impair the function of the choke pull-off.

 

[JackFish]

The bung on the bottom of the exhaust manifold has a metal tube and rubber hose that connects to the top of the carb on later models, like mine with a Holley 1946. It provides a source of hot air for cold winter start-ups.

 

[Frankenstang]

Thanks for the responses guys! Just came across this after some more searching...I was able find a picture of the stuff...
http://mansfieldmustang.com/05-10.JPG
Here's the page where it's listed as part of a 'choke stove kit: basic 9A714'
http://mansfieldmustang.com/EngineExhaust.html

The new reproduction 2in 'X' manifold I'm installing just has the clear passage as described, but I definitely see remnants of some similar 'meshy' stuff in the old 'fomoco' manifold I took off (along with a broken piece of choke tube that I tried to drive down through the passage last time I replaced one...looks like this stuff might have gotten in the way). I imagine it breaks down or disappears over time cause I've not seen it in other old manifolds or heard of it referenced. The fomoco manifold I took off is not that old of a replacement though (relatively speaking)...brand new 15+ yrs ago when you could still get ford parts for these cars. Another interesting thing is the fomoco manifold I'm replacing (for the reproduction 'x' type w/more flow) shows near zero signs of expansion (even with at least a solid 75+k on it)...I'll have to add a pic later.

So all this has got me wondering what's the real purpose of this filter/mesh Could it by chance be intended to retain heat in the passage (heat sinkish) as well as keep out larger debris? Would that make the passage less likely to bloat & rupture over time given less super hot/cold air proximity?

Assuming it was some type of filter for small particles or some such I just shoved a piece of stainless steel screen in from the bottom before installing the new manifold this evening (if nothing else it will inhibit dirt dobbers around here). I think I'll contact these Mansfield Mustang folks and see if they can tell me what it's made of, how much they charge for a chunk of it, and maybe it's purpose. Thanks again.

 

[ludwig]

I think I'll contact these Mansfield Mustang folks and see if they can tell me what it's made of, how much they charge for a chunk of it, and maybe it's purpose.

And they will say, "Oh, that's just something to make little Ford Sixers ask questions."

 

[Frankenstang]

I think I'll contact these Mansfield Mustang folks and see if they can tell me what it's made of, how much they charge for a chunk of it, and maybe it's purpose.

And they will say, "Oh, that's just something to make little Ford Sixers ask questions."

Eric, yes they very may well say that, but before they pat me on the head and send me on my way I'd have to remind them it's good enough for the BIG blocks

Another reference...
http://www.samsgarage.net/Chokestove.htm
And the same kit through MU...
https://www.mustangsunlimited.com/itemd ... y=EMUSTANG

I just might find the need to spend $23.50 with them in the name of 'scientific experimentation' :roll: provided they're not too condescending (the temperature idea has my brain itching...but maybe that's just the 105* heat-humidity factor we've got going here). Seriously though adding the cap w/inlet to the bottom opening would reduce the warm air inlet into the manifold passage to what appears to be the equivalent of the auto choke vacuum port in the carb body...wouldn't an inlet that small be even less likely to need this piece as a 'filter' function :

 

[JackFish]

Since the passage is designed to provide hot air, I would suggest that it functions as a passive heater coil.