Cliff's Quadrajet Parts and Rebuild Kits
General Category => Quadrajet Carb Talk and Tips => Topic started by: Cadman-iac on October 03, 2025, 03:18:42 PM
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Can someone please tell me what the specs are for a 17058204 Q-Jet?
If i read the book right, this fits a 78 350 Chevy with federal emissions.
If possible, I need everything so I can verify that this one hasn't been tampered with.
Thanks in advance for any help you can offer.
Rick
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Anyone have the specs for this?
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I have the 1978 Roch specs book. I’ll look.
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I have the 1978 Roch specs book. I’ll look.
Thanks, I'd greatly appreciate that.
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Nobody?
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Here are the specs i have found on the 17058204:
(Airvalves are measured from back edge of open valve to the back side of chokeblade housing).
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Here are the specs i have found on the 17058204:
(Airvalves are measured from back edge of open valve to the back side of chokeblade housing).
Thanks Kenth, much appreciated.
I got this one in a partial disassembled state, so I didn't know what to expect. The main jet size is surprising, but I guess with the air bleed sizes, it makes sense.
Many thanks.
Rick
So if you don't mind looking it up, what are the specs for the California version of this, I think it's a 17058504.
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Here is the California 17058504 unit:
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Here is the California 17058504 unit:
Wow! quite a bit of difference. I'm surprised, but then again, no, im not. California really screwed stuff up back then, and probably still do.
Thanks for this, very helpful.
On a related note, each of these carbs are listed as fitting several types of vehicles in 78, from an El Camino to a truck.
Being different vehicles, and therefore weights, would the calibrations be different for each application?
Or because the carb number is the same for each vehicle type and weight, the calibrations are the same?
Does that 3 letter code on the carburetor mean a specific calibration, or am I way off base here?
Thanks for your help,
Rick
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Here are the specs i have found on the 17058204:
(Airvalves are measured from back edge of open valve to the back side of chokeblade housing).
Kenth,
I forgot to ask about the float settings for these. Would you mind posting those for me.
Thank you very much.
Rick
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Here is the California 17058504 unit:
Where do you find that info?
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Kenth,
I forgot to ask about the float settings for these. Would you mind posting those for me.
Thank you very much.
Rick
Rick,
float setting is 15/32" for both units.
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Rick,
float setting is 15/32" for both units.
That's great, thank you very much Kenth. Have a great weekend.
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I am surprised by the 17058504 California specs. Seems like a 71 jet with .120 air bleeds would be extremely lean at full throttle with CH secondary rods.