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Discussion Starter · #1 ·
When I bought my 66, the previous owner had replaced the carburetor with a later model 1100 that he said came off of a Cougar. The car runs fine with the carb but the fuel mileage is pretty bad. I removed it today and found that it does not have a spark control valve and the body is not threaded for one so, I am guessing they deleted it later in production? The bowl vent has also been deleted. The main jet size is 69. Looking in the 66 Ford service manual, the 69 jet would be correct for a 3 speed but, this is a newer carburetor. I found an original 66 3 speed 1100 and cleaned and installed a master kit from Mikes in it but cant get it to run right. It idles great but bucks and snorts when I accelerate. I spent a day trying everything I knew to try with it but could never get it to run right so I re-installed the Cougar carb. Now, after thinking about it, Im wondering if my timing was off with the original 66 carb because it does have a spark control valve. I never thought to check the timing when I had it running with that carb. I wonder if it was a timing advance issue causing the bucking. It ran like it was super lean. Could juts be a bad carburetor too. Any ideas?
 

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eBay is selling new china knockoffs of the 1100, and Holley 1904. Maybe try one of those? As for the cougar carb without SCV, you could upgrade your ignition to a duraspark distributor and box, and run cougar carb...that is my recommendation. I also run a Daytona universal carb (1904 knockoff) and duraspark ignition. Runs great!
 

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Check to make sure that you have the correct Distributor also. You should have a '64-'66 Load-O-Matic disty. Post some pics of what your have so that we can see if its correct for your car. The Correct Carb and Distributor should be a matched pair. Since you have a 3-speed, You can use either the Original type 1-Dashpot Autolite 1100 (Non-IMCO) carb with Spark Advance, or you can also use the C4 Automatic 2-Dashpot Autolite 1100 (Non-IMCO) carb with Spark Advance. Either one will work fine with your Manual 3-speed, and 200 cid six engine.

:eek:)

Tony K.
 

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I'm still wondering what Cougar ever had an Autolite 1100.....

Let's see some photos of the carb you found and rebuilt and the distributor breaker plate with the rotor removed.
 

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That is a Loadamatic distributor. It must be used with a carb equipped with an SCV and it appears that your carb has an SCV. And the Cougar was never equipped with an I6.
 

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Okay. You DO have the Load-O-Matic distributor and also a SCV-equipped 1100. Remember that the L-O-M distributor has NO mechanical (centrifugal) advance and relies on the vacuum signal from the carburetor to control ALL spark advance. Make sure you reset your base timing to spec (6*BTDC) and that the vacuum signal from the carburetor is as close as possible to the following:

Engine RPM Degrees Advance Vacuum Signal in/hg
1200 2 - 4 0.44
1600 10 - 12 1.80
2400 16-1/2 - 18-1/2 1.90
4000 20-1/2 - 23 3.80
Total Advance 31*
 

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Discussion Starter · #8 ·
I agree. Funny how well it runs with the non-SCV carb though. So, it should have ran with the used carb that I rebuilt correct? I checked everything 3 times and couldnt get it to run right. Ive rebuilt at least 50 carbs. Any ideas? Juts a bad carb or ?
 

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Discussion Starter · #10 ·
Okay. You DO have the Load-O-Matic distributor and also a SCV-equipped 1100. Remember that the L-O-M distributor has NO mechanical (centrifugal) advance and relies on the vacuum signal from the carburetor to control ALL spark advance. Make sure you reset your base timing to spec (6*BTDC) and that the vacuum signal from the carburetor is as close as possible to the following:

Engine RPM Degrees Advance Vacuum Signal in/hg
1200 2 - 4 0.44
1600 10 - 12 1.80
2400 16-1/2 - 18-1/2 1.90
4000 20-1/2 - 23 3.80
Total Advance 31*
Thanks Woodchuck! Will the distributor advance have ported or full vacuum at idle ?
 

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Post pics and if you can find it the I’d number on the “Cougar” carb. As said above the classic Cougars didn’t come with the cal as an option so that carb is not off a Cougar. The non SCV carbs run well when properly set up, but they require a match8ng distributer. Your SCV dizzy does not have a mechanical advance so your spark curve is way off giving you poor acceleration and crappy gas mileage. The older NON IMCO sets can run very well too if you can find one in good shape. I have had mixed luck getting the carbs to tune correctly. Some are perfect, others are terrible. The distributer you have is designed for the new carb you found. Make sure the vacuum advance is functioning as it s the only control you have over the spark curve on a SCV car. It’s designed to work off a much smaller vacuum signal than the later cars.

How is your vacuum advance hooked up currently? It should be connected to the carb on a SCV setup, not the manifold. If connected to manifold, there is a good chance the vacuum diaphragm in the advance is shot.
 

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By your pics....Both look correct for your '66 3-Speed.

:eek:)

Tony K.
 

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Thanks Woodchuck! Will the distributor advance have ported or full vacuum at idle ?
Neither. The vacuum advance is connected directly to the carburetor which, with the Spark Control Valve, sends the distributor a vacuum signal modulated between manifold vacuum and venturi vacuum as shown in the image below.

 

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Discussion Starter · #14 ·
You guys really know your stuff! Ive got a bad vacuum advance. I dont know why I didnt think to test it earlier . I'll try to find one locally and then re-install my rebuilt carb and see what happens. There is no question as to why my fuel mileage has suffered! I'll report back soon. Thanks!
 

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Discussion Starter · #15 ·
I have re-installed the rebuilt carb and when I measure the vacuum , Im only getting 4lbs where it goes to the distributor. Does that sound right? I did install a check ball in the passage at the SCV. One drawing showed a ball there and one did not. Could that be the issue?
 

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Discussion Starter · #17 ·
I found one locally. I do need to know the vacuum requirement for it though. Im getting 4 hg from the carb.
 

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The vacuum charts for the different distributors are in the back of the ignition section of the shop manual.

This is for a C5DF-12127-E distributor:
66-vacuum_advance.jpg
 

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Discussion Starter · #19 · (Edited)
Thanks! UPDATE:. I installed the new Vacuum advance and it is running much better! Acceleration is the best its been. The only issue I have now is a slight miss under light throttle between 30-45 mph. I dont feel anything at 70. Timing is set to 6 degrees. I have a 69 Main Jet installed. Any thoughts? I wonder if I should bump the timing up a bit.
 

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Discussion Starter · #20 ·
Almost forgot. I did remove the check ball in the spark valve circuit which brought the vacuum up to 8 hg. Now that I see that 3.8 hg is the maximum needed, should I put the check ball back? Could that be the surging issue under light throttle?
 
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