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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Sounds more like an ignition problem right off the top of my head. To me.
 

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Discussion Starter #7
Sounds more like an ignition problem right off the top of my head. To me.
new plugs, wires, distributer, rebuilt carb twice, added new carb, new coil, checked for vacuum leaks, checked for wires arcing, adjusted valves, checked torgue on head bolts/intake, did timing starting at 6 to 20 initial and all in at 32-42 degrees at 2800-3000 rpm.

Only thing I didn’t do is a leak down/compression test.
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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21,399 Posts
I'm suspecting you haven't put it on an ignition scope? Few people have access to such. I bet one would be very informative. It's kind of what they are for, to bypass the guesswork.
 
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Discussion Starter #9
That is correct. March 9th it’s scheduled to be looked at by a professional with the correct equipment.
 

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I am actually considering a sniper efi 2300 system.

I have been trying to track down a rough idle/miss/stumble. I’ve done everything I know to do to find it
Have you tried using a timing light on individual cylinders to see if you can isolate which one(s) are misfiring?
 

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I have tried that. All appear to be firing the same.
Then I'd start looking at a bad spark plug. You don't have a header/manifold flange exhaust leak, do you?

FWIW, I'd throw a vacuum gauge on it and check the needle movement.
 

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Discussion Starter #13
No exhaust leak. I have used a vacuum gauge on it many times. Typically runs in the green at 19 inches of vacuum. There is a slight flicker of the needle.

The miss fire/stumble/rough idle is worse in drive and idling.
 

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No exhaust leak. I have used a vacuum gauge on it many times. Typically runs in the green at 19 inches of vacuum. There is a slight flicker of the needle.

The miss fire/stumble/rough idle is worse in drive and idling.
Is it a constant miss or does it "float"?
 

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More like a float or flutter. When hot, in drive, at a light it gets worse.
You might want to have a look down the carburetor throat, at idle, to see if the fuel is properly atomizing or you're getting collections of droplets that plop into the intake plenum. Could be fuel temperature too high or some kind of internal defect/air leak, etc.
 

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Discussion Starter #17
You might want to have a look down the carburetor throat, at idle, to see if the fuel is properly atomizing or you're getting collections of droplets that plop into the intake plenum. Could be fuel temperature too high or some kind of internal defect/air leak, etc.
will take a look. Exterior of carb at the float bowl is 110-115F. Carb spacer
 

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Discussion Starter #18
Stock carb spacer is 150F. If I spray brake clean at throttle shaft motor dies. Throttle shaft doesn’t seem to have any play in it. Operates smoothly.
 
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