CK5
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Correct ignition timing

Manifold vacuum advance. I haven't checked total timing again yet.
When I had it at 11° the idle was only 750.
I don't have any type of controller on the distributor yet.
 
My experience is aftermarket vacuum can will move the vacuum advane 20°. The mechanical must make up the difference.

Mechanical advance wieghts are free and move easily? The rotor shaft will move several degrees counter clockwise and snap back ?

Is this Holley a carb you bought new ? Or a new to you used holley?
 
The holley came o.n the truck I bought but never really ran. Just enough to have some dried up fuel inside it, so I rebuilt it.
 
These issues are why I stopped trying lol.

I'll make my carb'd stuff run good enough to drive, and drive it to the race shop and pay them $100 to set the timing and carb. :waytogo:
 
on vacuum sec holley there is a link rod between the primary and secondary, and a coil spring on the secondary throttle shaft. if the link rod is binding or bent incorrectly it could be holding the secondary blades open enough to cause the high idle.
 
on vacuum sec holley there is a link rod between the primary and secondary, and a coil spring on the secondary throttle shaft. if the link rod is binding or bent incorrectly it could be holding the secondary blades open enough to cause the high idle.
Ok, I will check that. Thanks again Wes !
 
Well I like to learn as much as I can about my hobbies. I'm a nerd like that
I studied up on it, and tried, and tried, and tried , and tried, and eventually got good enough to make em run, and run decent enough to go down the road. Then I take it to the guys that know it second nature, and let them tweak it, is what I was saying lol.
 
So I pulled the carb and took some pics. Let me know if I have something wrong please. The back of the flange on the intake looks like it might be leaking. But I'm not sure what that discoloration is.

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Gasket not 100% showing imprint + dark color = possible leak point .

Get a thick gasket / check carb pad with machinist stright edge for flat .

Then if good its in the carb .
 
holley 2a.jpg
red arrow need to be @.015" slop between rod and back of slot. Check with choke open and high idle screw off the choke cam steps.
holley 2b.jpg
This looks like it's jammed up.

I just found improperly assembled choke linkage on my buddies Impala's 1406. someone had a lever on the opposite of a tab. How they did it still has me scratching my head, not some you need to remove for a simple clean out
 
Gasket not 100% showing imprint + dark color = possible leak point .

Get a thick gasket / check carb pad with machinist stright edge for flat .

Then if good its in the carb .
That’s almost exactly what I was gonna say. That gasket is suspect. My advice, get a new thick gasket, be nice to it.

I’ll be dead honest, the only time I’ve had a good running Holley carb, was when I was a teenager(many, many moons ago)
I couldn’t get mine to run correctly either. I remember assuring both primary and secondary butterfly blades were closed completely, by tweaking the actuator rods on both sides of the throttle body.
Then replaced the secondary jets one size up from recommended. Then, disconnecting the upper secondary butterfly blade actuator rods, and safety wiring the upper blades wide open. Then plugging all vacuum parts accept the ported one to the distributor.
And, the choke linkage totally disconnected.
That way, when you nailed the throttle the secondary’s were in full operation, along with the primary’s already in use. When the transmission kicked down, the engine would rocket straight to the moon. But, at idle, with the primary’s butterfly blades closed, it would idle at 700 rpm all day.
Was it correct? No. Did it work? Yes.
Win! For a 16 year old kid relying on what I saw other people doing to get their junk to run, I was totally happy with it.
As a second idea. I had a real problem with worn throttle rod vacuum leaks, I’m not sure what their called the rods the run horizontally through the venturies, the butterfly blades attach to them. Where they pass through the side of the carburetor itself, after a while Holley’s wear out there. They make a teflon repair kit for it. Essentially, it’s just a small piece of teflon that fits around the shaft into the outside of the carburetor to seal up the worn gap. It’s a PITA to do, because you have to take all the linkages off the carb to install it correctly.
And like Wes said, use a machinist straight edge and a file to assure the bottom surface of the carburetor base is perfect flat.
 
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