Quadrajet questions

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BJedi76

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i recently tried another forum, but i felt that i was not exactly welcome. i hope this goes better.

anyway... i have an; ‘86 GMC Sierra Classic 1500 4x4 swb.

i has been “Frankensteined”. it currently has a 1980 Canadian 350” out of a california 1 ton van. it has a 700r4 trans.

It has a 17066559 Rochester Q-jet (M4MC i think).

someone from the other forum said that i have the “dreaded hacked commercial rebuilt) carb. & it’s not rebuildable.

can someone Knowledgeable please confirm or deny this? ...& explain why?

is this why i’m having so much trouble identifying my carb?

is there better Q-jet than others?
 

C10MixMaster

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ZZ4 350
i recently tried another forum, but i felt that i was not exactly welcome. i hope this goes better.

anyway... i have an; ‘86 GMC Sierra Classic 1500 4x4 swb.

i has been “Frankensteined”. it currently has a 1980 Canadian 350” out of a california 1 ton van. it has a 700r4 trans.

It has a 17066559 Rochester Q-jet (M4MC i think).

someone from the other forum said that i have the “dreaded hacked commercial rebuilt) carb. & it’s not rebuildable.

can someone Knowledgeable please confirm or deny this? ...& explain why?

is this why i’m having so much trouble identifying my carb?

is there better Q-jet than others?


Looks to be a regular Qjet used from 80-85 i dont see any reason it cannot be rebuilt. http://www.carburetion.com/CarbNumber.asp?Number=17066559
 

Doppleganger

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I have this one (professionally rebuilt) - was out of my 85 K20 which was a west coast truck with all the Cali emissions choking it.

Not trying to peddle anything and no idea how hard these are to find or whats 'special' about a Cali emission carb. Its here and un-needed is what I'm getting at. :hat:

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1973c10

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Welcome :boti:
 

75gmck25

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K25 Camper Special TH350 NP203
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5.7
I've found that about 50% of the Quadrajet info you find in postings online is from someone who is trying to justify why they hate them. There is a lot of incorrect and misleading info in the "old wives tales" about why a Quadrajet is bad or is hard to tune.

This is one of the last quadrajet models before they added electric or electronic controls, so its a very good carburetor to rebuild. I would switch to an electric choke, and then use a rebuild kit from Cliff Ruggles to get it running right. If you send him the drivetrain specs, in the rebuild kit he will send you jets and rods that will work well with your engine.

You can also mod this carburetor to make the (adjustable part throttle) APT screw accessible, which allows you to tweak the transition to power mode. You can also use different air bleeds and/or modify the air flaps to make it work better with higher performance cams.

I have a similar 17080213 carburetor on my GMC K25 350/TH350.

Bruce
 

Snoots

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X2 on Cliff Ruggles. You can learn a LOT from his book too. And he loves fishing!
 

Old77

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350/350/454
:welcome: I've moved this thread to a more appropriate section to get better exposure to your questions
 

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