Recommend carb for 5.7 350
 

Hi All,
I am currently looking for a new carb for my truck. I have a q-jet in mine but after taking my truck in for a some timing work and a vacuum leak my mechanic said my carb is bad. He said 2 of the valves are not opening up at all and it would not be wise to rebuild the carb.

This is the current carb that I am running (Q-jet 17081206 1171 DDJ)
Q-jet Carb

He recommend that I look for something with 500-600CFM.

Would something like this Holley work:
Holley 4160 Carb

Re: Recommend carb for 5.7 350
 

Get a new mechanic. Unless there is physical damage, the Qjet is a fine carb in capabale hands. Is is the best of both worlds. Small primaries for economy and large secondaries for power. Build the Qjet.

If you must get a new one, I would (and have) dump the carburetor and convert to TPI or TBI fuel injection.

If you are dead set on a carb, and don't want a Qjet, get a 600cfm vacuum secondaries Holley. Stay away from Edelbrock IMHO.

Re: Recommend carb for 5.7 350
 

X2 on get a new mechanic. Quads don't have valves. They've got secondary throttle plates. Yours likely won't open because the choke lock out is on.
If you get a new carb whether a holley or Edelbrock you'll need a new intake or an adaptor to put the new carb on yours. One like this.
Keep the quad. It's likely the best for your truck.
Edelbrock 2696 Four-Hole Square-Bore to...

Re: Recommend carb for 5.7 350
 

I had a feeling his suggestion was a bit off.

I honestly did not mind the q-jet and I am pretty sure it has been running like that since I got it. I thought the PO had rebuilt it but guess not.

So to fix it would I just need a rebuild kit? Similar to this one: Cliff Ruggles Rebuild Kit

Re: Recommend carb for 5.7 350
 

I put an Edelbrock remake of the quadrajet and have to say it performed flawlessly for me.

I ran it till I went FI now it is on my 69 1 ton. Does need a little tuning on it now but it's 15 years old.

Re: Recommend carb for 5.7 350
 

I could have not remembered properly on what he said was not functioning but 2 of the plates are not opening and I have seen this as well when I was working on the distributor.

So would I just need a new intake or adapter to get mine working and need a rebuild kit?

Re: Recommend carb for 5.7 350
 

THat kit would work.
But!!
No offence but doesn't sound like you have any experience with carbs. Cliff will rebuild yours. Check on his web page under 'services'.
If you want to tackle it yourself we can certainly provide you with a ton of links that show you how.

As always, take some pics of your carb for us.

Re: Recommend carb for 5.7 350
 

You hit the nail on it, I do not have any experience with carbs at all. I have his rebuild book and think I can tackle it after reading up on how to do this. Pretty much I have learned a lot from owning this truck.

Here are a couple of pics of the carb. I'll get some better ones later on tonight.
Attachment 1145151

Attachment 1145152

Re: Recommend carb for 5.7 350
 

Well from what I see your carb is a lot cleaner than normal ones. Coulda been rebuilt.
When you take pics pull the air cleaner off. Take a pic from both sides and the front. Don't need close-ups like those.
You might only need a couple minor tweeks to fix it.

Re: Recommend carb for 5.7 350
 

Those are expensive kits! I got one for $20 at autozone.

Re: Recommend carb for 5.7 350
 

Double the price but more to the kit. And the best quality too.
You get what you pay for John.

Re: Recommend carb for 5.7 350
 

Very true but I hate quadrajets!!!!! If this body I am soaking in cleaner all week doesn't work to replace the body I have with that stripped fuel inlet thread in mine I will happily be replacing it with a holley! I can rebuild and tune a holley blindfolded but these quadrajets just seem overcomplicated.

Re: Recommend carb for 5.7 350
 

[QUOTE=utee05;6241097]You hit the nail on it, I do not have any experience with carbs at all. I have his rebuild book and think I can tackle it after reading up on how to do this. Pretty much I have learned a lot from owning this truck.


You said, "I have his rebuild book and think I can tackle it after reading up on how to do this." Since you have the book, 1st of all study the 'linkage pictures' and adjust/set yours accordingly/properly--not talking about pedal-to-carb linkages; but linkages like the choke--and other linkages--disallowing secondaries to open until choke is wide open(made that way by design).

Study them carefully, as I've seen some parts left off or set to intentionally cause secondaries to not open, for whatever reason like trying for better mpg(??). Sounds like it might not need rebuilding, esp. as it looks so clean that it probably has recently been re-built, just possibly improperly re-assembled. If it performs well exc. for the back 2 barrels not opening, you may very well have a simple, external fix. A parallel, I think, would be "if a tire is leaking air thru the valve core, tire may NOT need removing and resealing!...but just a valve core replaced."

Another good thing to do is to get a good-operating, like carb, and compare its linkage-positions to yours. Maybe get a buddy at a parts house to let you bring yours in and just compare it to one of his rebuilt/new ones from his shelf. You'll possibly immediately see a distinct difference[and the problem]; and should you find the culprit, buy your buddy lunch one day--could be $ well spent PLUS increasing your friendship!

HTH, & loving those quadrajets--'closest thing to fuel injection in a carburetor'[NOT my constructed statement, but one I kidnapped from another poster with whom I totally agree]!
Sam

Re: Recommend carb for 5.7 350
 

Your statement is just too funny to pass up: I've seen a few q'jets that looked like someone DID rebuild them blindfolded. And, I agree they are a bit more complicated than some, with so many systems and adjustments that need to be to coordinated. But my belief is they have so many 'extra', adjustable functions that they can be (better?) finely tailored to each individual engine's needs. Kinda like the simpler carbs may merely perform close enough to what engines need that they approach a one-size-fits-all, albeit not optimally--all this IMO, and open to disagreement.
Sam

Re: Recommend carb for 5.7 350
 

Cliff currently has over a year waiting list...

Cliff's kits are the best out there. An Autozone is decent, but to trult tweak a Q jet, Cliff's kit is tops.

Agreed! A properly set-up Q-jet is superior to any Holley, Carter, or other 4 barrel carb in terms of being good for economy AND power production. That is not my opinion - it has been proven time after time. If you want to go fast at the track or just want to throw a carb out of the box on an engine and go, the Holley is your carb. If you want a carb that gets good mileage, and makes excellent power, and supplies the engine with the proper cfm it needs at all throttle positions, the Q-jet is where its at.

Re: Recommend carb for 5.7 350
 

And if you like to 'dare to be different' and are a true follower of 'Mores Law' then you temp fate and tinker with running 2 quadrajets in tandem on a dual quad intake. I did way back when. Ran a pair of carter afb's and switched to quads just to see how it would work. People like the sound of the secondaries opening on one quad. You gotta feel and hear the sound of two. Almost like the sound of a pair of afb's on a hemi!
I ran the front carb as my secondary. Cranked in at 40% opening of my rear primary.
Thanks to the apt they were tuneable. And an assortment of secondary hangers.
Great fun. One of the best carbs ever built.
Definition time: 'More's Law'-- if some is good, more's better!

Re: Recommend carb for 5.7 350
 

Geezer, I'm old enough to remember that wonderful, moaning sound of the back two bbls opening on the old AFB's back in the early 60's--before q'jets were heard of (at least by me). We'd change the 4GC(?) and smaller 250/hp 327-intake for the AFB and 300 hp/327-intake--man what a difference! Get on it for just a moment and let back off, and it would sound just like a person saying "want some"! ...hoping this is not too bad that it deserves editing; but that's exactly the sound. And the power increase was just phenomenal.

Did those AFB's have bigger secondaries than these new Edelbrocks? Seems I recall a VERY noticeable size increase between the primaries and secondaries--more so than present-day Edelbrocks. But, having blown out so many birthday candles, I'm kinda winded and may suffer from lack of oxygen to the brain:even if so, some of the memories I do recall are still exuberant--and priceless:lol:.

BTW: lotsa people working on q'jets have no idea what the APT is or that it even exists. [Yet may be good IF they don't know what to do with it--even if they have an adjustment tool.]
sam

Re: Recommend carb for 5.7 350
 

Most afb's had equal size throttles. You likely remember the secondary air door opening. The ones I built (from a big box of carbs and parts) were 500 cfm. The quads were your normal 725 jobs. Much more forgiving especially with the apt and adjustable secondary air door. WE better not let the apt secret out. LOL!!
One of my best memories is the late night sound of the local rich kid opening up all 8 barrels on his 69 hemi runner as he slipped around the corner and headed home. A pure adrenalin rush. Got to experience it myself from the drivers seat a few years later in a 67 hemi 4 gear gtx and a 70 hemi cuda.
Anywho, apoligies to Utee05 for highjackin' hgis thread!
Back to your regular programming!

Re: Recommend carb for 5.7 350
 

Sadly I do not know of anyone who owns a truck with a q-jet. They all seem to have holley's on theirs.

Here are some pics of the carb. Let me know if these help figure out what is going on.


Attachment 1145386

Attachment 1145387

Attachment 1145388

Attachment 1145389

Attachment 1145390

Re: Recommend carb for 5.7 350
 

[quote=luvbowties;6241697]I agree that it could have been possibly been rebuilt that way or incorrectly. I had been told it had been rebuilt when I bought it but was not sure, but from the comments it may have actually been.

Re: Recommend carb for 5.7 350
 

Hey what I have is a Holley I've had all the others carter edelbrock demon there's goods and bads to all. It comes down to how your motors built. If stock I would rebuild ur carb if it needs it or get a edelbrock or carter if its got some extras I would go with a Holley, but it really comes down to what u want and like
Posted via Mobile Device

Re: Recommend carb for 5.7 350
 

This one on mine has a remanufactured in 2010 sticker on it but I don't know who did it. I opened it up to check the float, needle and seat assembly as the truck was stalling at low rpm/stops and hard to start immediately after (suggesting to me it was probably flooding). Figuring it had all new parts internally, I just needed a basic gasket kit so I could open it up and see what was going on. I DID find a few things wrong- e.g. the needle and seat were not wired to the float assembly. But with my limited QJ experience, who knows how much I missed...

Hopefully I'll have the fuel inlet sorted out this weekend when I get home and will see if I have a good, complete carb. Then I need to get all my linkages straightened out. The job was supposed to take a few hours, not a week.... I took pictures but still.

I'd love to go aftermarket FI but too many other things needed on the truck to spend the money on that right now.....

Re: Recommend carb for 5.7 350
 

Nothing obvious stands out from your pics. Too clean not to have been rebuilt. Just no power to your choke.
So what does your truck run like?
How well does it start?
What's your timing set at?

Re: Recommend carb for 5.7 350
 

i like holleys......i run a 600 double pump.

Re: Recommend carb for 5.7 350
 

I'm in the "get a new mechanic" camp. The carb on my truck when I bought it was off a 78 Olds or Buick. Like you I explored rebuilding it myself (if you need more books on Quadrajets, just let me know :lol:), send it off to someone, etc.

To make a long story short, bought an Edelbrock Performer intake and the guy threw in a Quadrajet that he claimed he bought as a rebuilt carb, ran for 2000 miles in his Camaro then it sat on the shelf in his shop for five years.

I found a guy at a local shop old enough to actually know what a carburator is. He put a kit in the "rebuilt" carb, straightened out the plumbing and linkage now it runs like a champ. I had to give him $150, but as far as I'm concerned it was well worth every penny.