Yes, you absolutely need a primary choke pull-off, even with an electric choke.
Here is the breakdown of why that "25-degree" adjustment matters and how it works on your Q-Jet.
1. What the "Choke Brake" Actually Does
When you first start a cold engine, the choke plate is snapped shut. Once the engine fires, it needs a gulp of air immediately or it will "flood" and die from being too rich.
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The Pull-Off: This is a small vacuum diaphragm on the side of the carb.
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The Action: As soon as the engine starts, manifold vacuum hits that diaphragm, which pulls a linkage to crack the choke plate open a specific amount (that’s the 25 degrees you saw).
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Electric vs. Vacuum: The electric part of your choke only controls how fast the choke eventually opens all the way as the engine warms up. It does nothing to provide that "instant crack" needed the second the engine fires.
2. Why You Might Not Have Seen It
On many Quadrajets, the primary pull-off is mounted on the front passenger side. If you didn't see one in the video or on your carb:
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Missing Parts: It’s common for these to be removed or broken on older units.
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Integrated Units: Some later models have the pull-off tucked away or use a dual-break system (Primary and Secondary).
3. Setting the Angle
The "25 degrees" is a general spec, but every Quadrajet code has a specific "Choke Pull-Off" or "Vacuum Break" setting (usually measured in inches or degrees).
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If the plate stays too shut (less than 25°), the engine will blow black smoke and stumble.
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If it pulls too far open (more than 25°), the engine will lean out and die right after start-up.
Summary Checklist
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Do you need it? Yes. Without it, your cold starts will be very difficult.
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The Adjustment: Use the screw on the pull-off linkage to ensure that when you apply vacuum (or push the plunger in by hand), the choke plate opens to that specified gap.
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The Electric Choke: Keep it! Just make sure it has 12V switched power so it relaxes and fully opens the plate after about 5 minutes of driving.
