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  • 1974 - 1978 Mustang II Talk & Tech

Weird Device On Firewall.

  • Thread starter Thread starter Bmwz389
  • Start date Start date Mar 2, 2010
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78CobraII

Moderator
Jul 31, 1998
1,808
8
39
Birmingham, AL
Mar 18, 2010
#21
  • Mar 18, 2010
  • #21
They are pretty much all the same internally other than the later computer feedback carbs for CA.

The R number should ID the rebuild kit that you need. If you are not worried about originallity, mix and match parts to get what you want. My '76 carb had both the coolant heater and the electric heater. The electric heater goes up against the choke mechanism so that it brings the choke off quickly while it takes the coolant a while to reach temp. The coolant housing fits over the electric heater with a plate between to seal the water away from the heater.

These are designed by Weber, manufactured by Holley, sold by Motorcraft, and used by Ford. Sheesh...

A tuning book would help select jets, bleeds, cams, etc., especially if you are going for increased performance. I fiddled with mine for years, but probably did more to hurt fuel mileage than to increase performance! There weren't tuning books in the early '80's, so I modified it a bit each time I tore it down for a rebuild...smoothed the choke entry area, drilled the main jets, swapped air bleed screws. But it didn't make much of a diference because I had the wrong cam.

A hot-rodded 2.3L really benefits from more carb like the 350 CFM Holley (non-progressive) 2bbl or the Holley 390 cfm 4 bbl, but you have to have a high lift cam to make use of the extra cfm. The 5200 would be a great carb to use on a multiple carb manifold (if anyone made such a beast).

In 1980, "Hot Rod" magazine build a 2.3L in multiple stages and ended up with over 150 streetable HP (Stage II) and over 200 in race trim (Stage IV). Circle track guys are still building them this way , but have some better parts these days.

You are rebuilding an 1800?
 

Bmwz389

Member
Dec 5, 2009
74
0
7
Mar 18, 2010
#22
  • Mar 18, 2010
  • #22
I wasn't planning on rebuilding anything yet. I just need to get him running and starting for a daily for now. I need a solid foundation before I build anything, and I already have plans to build a motor this summer or following winter anyways, so most of the spare money is going to that motor for now!

It seems to just be an odd choke issue, and then I can dial down the idle to be at standard and make sure my mixture is right.

Soooo, now that we FINALLY know what the hell carb is on this thing haha. Is the only option to find the choke assembly at a junkyard? I can't buy the part new (so I know it works)?

Also, if you can develop more of which system to run, electric or heater, which works best. Or if they work best together? I don't know much about carbs in general, but I think I can handle the choke situation for now haha.

Thanks again! Yall have been a tremendous help so far....

- Brandon
 

Bmwz389

Member
Dec 5, 2009
74
0
7
Mar 18, 2010
#23
  • Mar 18, 2010
  • #23
^^^^ Oh and the whole 1800 thing was a post I copied over here, to help out some more if it did haha.


I wouldn't mind havin an old Pinto though, they're so goofily kickass haha.

- Brandon
 

78CobraII

Moderator
Jul 31, 1998
1,808
8
39
Birmingham, AL
Mar 19, 2010
#24
  • Mar 19, 2010
  • #24
Sorry, I didn't realize that that block of text was a quote.

If remember right the Chilton's MII manual had a decent section on setting the choke. I would dig that up and give it a try. Just be happy that we have an electronic ignition system so that you don't have to set point gaps and that we have hydraulic lifters so that you don't have to set lash!

One thing that I remember about messing with this carb was that with all the linkage hanging off side, you really had to keep it clean (with carburator cleaner) and lightly lubed (with WD40) in order to keep the choke and throttle action smooth.
 

Bmwz389

Member
Dec 5, 2009
74
0
7
Mar 20, 2010
#25
  • Mar 20, 2010
  • #25
Yeah I definitely need to order one since nobody has one in stock (Chiltons).

I may have to spray it down on the linkage area and lube it like you advised, and see what that does.

Also, is the choke technically called a "Choke Pull Off"? And does the "Choke Thermostat" Sit inside the choke housing seperately? Or is it part of an automatic choke?

Thanks!

- Brandon
 

78CobraII

Moderator
Jul 31, 1998
1,808
8
39
Birmingham, AL
Mar 30, 2010
#26
  • Mar 30, 2010
  • #26
Ha! I haven't been under the hood of my project car ('78 Ghia, 2.3L, 4speed) for a while, but when I did, I found that I had a similar weird device on my firewall.

Also, my carb has only the electric choke heater, and not the water heater circuit. My '76 2.3L Holley 5200 is a significantly different carb from my '78 with different hardware hanging off of it and lots of additional vacuum lines (like the firewall device).

It was running when I started working on it years ago, but I have a long way to get back to that point.
 

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