unjunking the quadrajunk

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1970 Torino 429 Cobra Jet and 1971 Mustang 429 Cobra Jet.

Trucks. :rolleyes:

lol. wow, those were rare then. 1970 and 71, makes sense why they would use a spreadbore. everyone was hustling to meet c.a.r.b. and epa nightmares. dont ya know how they must have woke up the hidden power when they replaced with a good intake and carburetor! and gearing! but they would overpower the tires already, so maybe they didnt?
 

SirRobyn0

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LMAO sounds fun!

I did figure out my choke seems to be working properly. I do have to replace that c clip so the rod doesn't disconnect again. I have no idea how long that was disconnected so I basically never had the choke open up that whole time. Once i fix that hopefully some of my cold start issues are solved. Choke could probably use adjusting but I am not really sure how to do that yet.

Still need to check out float. I might pull air horn again later to take a look.
Let us know what happens as you get into the repairs.
 

AuroraGirl

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I got a Quadrajet level 2 from national carburetor last year I'm getting rid of for $200 plus shipping(about $20)if you don't wanna mess with it. Just let me know.

It's ready to slap on and fire up. It was working great but, I just put in a BBC 454 and don't need it now.
what you running on big block?
 

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Id like to point out, that amount of barrels doesnt mean performance per se. My uncles sbc for midwest modified dynos about 320hp at 4000rpm iirc, and he has a 2 barrel holley(made for race application) and i think his cfm is 500. People too quick to assume more cfm=better. I have 650 cfm but i can assure you im likely under 250hp with an otherwise stock motor. I think cam and valve changes mean more to your numbers than barrels and CFM. Now, there is a point where CFM and barrels could limit, but i wouldnt think many of us hit that in our day to day.

Also to point out, his engine runs on race gas(107 octane iirc, leaded). So not like a street build, but i think we over emphasize the need for a big bad carburetor.
 

Turbo4whl

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Not that the Q-jet is all that complicated, but people don't take the time to understand it..............
........ actually a brilliant piece of engineering........Finding tuning parts is what limits them for high performance use ...

Yes. An example, as soon as you install headers and a free flow exhaust, you need a richer mixture to gain the full benefits of that new exhaust.

Getting the tuning parts, jets and rods.
 

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Id like to point out, that amount of barrels doesnt mean performance per se. My uncles sbc for midwest modified dynos about 320hp at 4000rpm iirc, and he has a 2 barrel holley(made for race application) and i think his cfm is 500. People too quick to assume more cfm=better. I have 650 cfm but i can assure you im likely under 250hp with an otherwise stock motor. I think cam and valve changes mean more to your numbers than barrels and CFM. Now, there is a point where CFM and barrels could limit, but i wouldnt think many of us hit that in our day to day.

Also to point out, his engine runs on race gas(107 octane iirc, leaded). So not like a street build, but i think we over emphasize the need for a big bad carburetor.

VERY true. Dodge loved to run 2 barrels on their 360's in the 70's I had one in a class c motorhome, at one point I swapped on an Edelbrock, but eventually went back to the 2 barrel, the main issues were I'd bought an aluminum intake that set the carb so high under the dog house I had to have a short air cleaner, and I couldn't tell the difference in seat of the pants performance.
 

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You can also hog out a 2bbl Rochester and they perform almost as well as a Qjet. We had a street racer bud named 2 barrel Bill. He was kickin' ass and taking names. He got all the good races cuz everyone just knew they could beat him. Nope. He'd whip their ass. He dialed in his biggo cam to where you could hardly tell he had a big cam in it. Then recurve the dizzy advance, gasket port the intake runners and head ports. It was a running muhfugger. He did end up sneaking some NOS under the intake that noone seen too. How do you get a 2bbl in the high 12's? NOS. A wet NOS set up at that. It was a plumbing beauty under the intake.

2 barrel Bill must have been an old timer, like the guys that would run a high decked Chevy 6 truck motor...... Those guys knew that HP is only a number and that torque wins races. The only problem here is that setup is as bad as a Holley, you won't drive past many gas stations.
 

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Quadrajets can be a good street performance carb it’s just hard to get the tuning jets. I spent years collecting my assortment. A lot of guys don’t know they come in 750cfm and 800cfm which can be hard to find. Guys running in the NHRA Stock class have got the tuning down and there Chevys make some serious hp while using a Qjet.
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72velle

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I have never and will never claim to be an expert on carbs and am driven by making the right choice on the first try since I can't afford to make mistakes. Lingenfelter wrote a book on how to build small block horsepower and his carb recommendations are pretty insightful. Choose your carb based on your needs. Want to go fast and don't care about gas mileage, Holley. Want a good top end or a good bottom end, Edelbrock. Want to get good MPG but have that kick in the pants when you jump on it, Q-jet. Get one set up right for your needs and you don't have to play with it.
 

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I have never and will never claim to be an expert on carbs and am driven by making the right choice on the first try since I can't afford to make mistakes. Lingenfelter wrote a book on how to build small block horsepower and his carb recommendations are pretty insightful. Choose your carb based on your needs. Want to go fast and don't care about gas mileage, Holley. Want a good top end or a good bottom end, Edelbrock. Want to get good MPG but have that kick in the pants when you jump on it, Q-jet. Get one set up right for your needs and you don't have to play with it.
 
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Quadrajets can be a good street performance carb it’s just hard to get the tuning jets. I spent years collecting my assortment. A lot of guys don’t know they come in 750cfm and 800cfm which can be hard to find. Guys running in the NHRA Stock class have got the tuning down and there Chevys make some serious hp while using a Qjet.
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you got it figured out! give yourself a slice of raisin pie!
 
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2 barrel Bill must have been an old timer, like the guys that would run a high decked Chevy 6 truck motor...... Those guys knew that HP is only a number and that torque wins races. The only problem here is that setup is as bad as a Holley, you won't drive past many gas stations.
mph at the end of the run is a direst result of HP. et is a direct esult of tq. unless of course, you were running a setup and didnt understand tuning. as bad as a holley is a stupid statement by someone who never understood tuning. i can see your car at 14.97@ 82mph.
disagree? show me your slips.
 

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Have to say the title of this thread upsets me. Quadrajunk? Really? It's one of the most versatile carbs ever made. And, "Holleys aren't reliable and not great for the street." Total BS on both counts.

It's the bad mechanic who blames his tools, or in this case, his engine parts.

If you want to start a thread asking for help, how about trying, "I'm having trouble with my carburetor".
 
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82sbshortbed

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Here's a question, (not being a smart ass but, maybe a *******) anyone run a Quadrajet on a BBC?
 

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