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1970 carb

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Old 05-15-2014, 06:47 PM
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wbriney
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Default 1970 carb

My 1970 seems to be running a little rich. The car came from Montana and i think the car was adjusted for the higher elevation. I live at sea level.

Can I easily adjust the carb or does it need a whole tuneup?

Thanks
Old 05-15-2014, 09:10 PM
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johnt365
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So if the carb is in good working order but just tuned for higher altitude using a different rod and jet combination, I would think you could make the adjustments with the carb on the car.

On a Quadrajet, the idle screws are easy right in the front of the car and can be adjusted for max vacuum with an inexpensive or even rental gauge.

To get to the primary rods and Jets, the choke is disconnected, accelerator pump linkage disconnected from air horn and the top air horn must be removed.

If you are gentle you may be able to reuse the gasket but have one ready to go just in case.

I think the first step after the idle adjustment would be to take inventory of what your current primary and secondary rods and primary jets are . The parts are relatively inexpensive and Lars has a great white paper to help with the selection.
Old 05-16-2014, 08:17 AM
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jnb5101
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"Seems a little rich"? Before you start messing with the carb, find out for sure. Get a F/A ratio done.
Old 05-16-2014, 08:54 AM
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jrheyerly
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Originally Posted by johnt365
So if the carb is in good working order but just tuned for higher altitude using a different rod and jet combination, I would think you could make the adjustments with the carb on the car.

On a Quadrajet, the idle screws are easy right in the front of the car and can be adjusted for max vacuum with an inexpensive or even rental gauge.

To get to the primary rods and Jets, the choke is disconnected, accelerator pump linkage disconnected from air horn and the top air horn must be removed.

If you are gentle you may be able to reuse the gasket but have one ready to go just in case.

I think the first step after the idle adjustment would be to take inventory of what your current primary and secondary rods and primary jets are . The parts are relatively inexpensive and Lars has a great white paper to help with the selection.
Any chance of getting a copy of the Lars chart?
Old 05-17-2014, 11:05 AM
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lars
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Originally Posted by wbriney
My 1970 seems to be running a little rich. The car came from Montana and i think the car was adjusted for the higher elevation. I live at sea level.

Can I easily adjust the carb or does it need a whole tuneup?

Thanks
You have other problems. If the carb were set up for Montana, it would be running lean at sea level - not rich.

You can obtain my tuning papers by sending me an e-mail request.

Lars
V8FastCars@msn.com

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