Which carburetor?
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Joined: May 2007
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From: kansas city mo
Which carburetor?
Hi all. Just bought a 77 coupe which has the l48 motor. All stock with 48,000 on it. The car has been sitting for years and the carburetor is in dire need of replacement or a complete rebuild. The carb is a carter q/jet. I was wanting some opinions on which carburetor you would suggest as a replacement or should I go ahead and work with the carter. Any info would be greatly appreciated. Thanks in advance, Bob.T
Le Mans Master
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I'd go with the carb you have. A good rebuild by someone that really knows what's going on in there and can fix the common problems, it'll run better than new.
Race Director
Joined: Jan 2000
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From: San Jose CA
What's the part number on the carburetor? I didn't think Carter was casting QuadraJets that late, but I could be wrong. If it's an original late 70's carb it's quite good. You will not get much hp if any by spending hundreds of dollars on another carb.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Unless there is some really significant corrosion damage in or on the carb, it should clean up just fine and a rebuild kit and proper set-up and adjustment will yield the right carb for the job.
If you don't want [or feel compentent enough] to do that work yourself and would consider buying an Edelbrock AFB-type carb instead, please don't. Send an e-mail to Lars Grimsrud (V8FastCars@msn.com) asking if he can rebuild your Q-Jet. If he can, he will do a great job....it will be "right" when you get it back. His fees and shipping will likely be around the same or less than what a new Edelbrock with cost--and you don't really want the Edelbrock, IMO.
If you don't want [or feel compentent enough] to do that work yourself and would consider buying an Edelbrock AFB-type carb instead, please don't. Send an e-mail to Lars Grimsrud (V8FastCars@msn.com) asking if he can rebuild your Q-Jet. If he can, he will do a great job....it will be "right" when you get it back. His fees and shipping will likely be around the same or less than what a new Edelbrock with cost--and you don't really want the Edelbrock, IMO.
Last edited by 7T1vette; Aug 6, 2013 at 10:17 PM.
Racer
Joined: Jul 2013
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From: Leesburg VA
Was the stock Q-Jet a 600 cfm? I have a Edelbrock 1406 on my 74 350/auto, and have been talking with Ryan, one of my forum friends, about replacing it with a Q-Jet 750. I have found rebuilt ones at Jegs for $299.
John
John
Le Mans Master
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From: North tonawanda NY
The ones sold by edelbrock are actually Weber carbs made by carter and now edelbrock owns the molds and sent them overseas to china where they now make them.... if you look at the Carb body they still have the Weber logo molded into the side of them... its a true knockoff made from original 50 ? Year old molds.
Team Owner
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From: Crossville TN
Carter made lots of Q-Jets. Rochester couldn't make enough of them for GM and others. They are exactly the same except for the cast-in manufacturer name.
Most Q-Jets have 750 cfm capacity; some later versions have 800 cfm.
Most Q-Jets have 750 cfm capacity; some later versions have 800 cfm.
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Race Director
Joined: Jan 2000
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From: San Jose CA
And my answer would have mirrored Mike's exactly. I don't know which years that Carter was casting Q-Jets, just that they did. I don't have any in my "collection", but I've seen a few.
Thread Starter
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Joined: May 2007
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From: kansas city mo
Thanks for all the help guys. Definatly a carter. The casting says quadrajet mfg by carter for gm. Thanks 7t1 for the email info. I will be contacting him very soon for the rebuild.
Le Mans Master
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From: Oxford MA-----You just lost the game!!!!
I've never had occasion to have Lars do any work for me, so I can't speak from experience, but I will say this: I have never heard anybody complain about his work. Ever. And that's saying something.
Scott
Scott
Racer
Joined: Feb 2012
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From: Clawson Michigan
I would talk to Lars. I was in a time crunch wanting to go to the saint Ignace car show and cruise and installing my headers/ sidepipes and found out it was running lean afterwards. I ordered a q jet from kegs. So far it's worked out really good out of the box. This winter I am going to install a 383 and I am going to talk with Lars to get the right carb.
Race Director
Joined: Jan 2000
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From: San Jose CA
What's the P/N on the carburetor? Should be on the driver's side of the carb, facing forward. Will be a 7 digit number starting with 70 or an 8 digit number starting with 170.
If you can get pics of the carb all the better.
If you can get pics of the carb all the better.
Burning Brakes
Joined: Oct 2011
Posts: 956
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From: McDonough Georgia
The q jet is junk. I would immediately throw it away and get a Holley.
Carter made Q junk licensed from GM. Rochester isn't a company, its the town the GM carb plant is in. Somehow they started calling them Rochesters.
A lot of folks live in a CFM fantasy world. Just because the the Q junk is allegedly capable of 750 CFM, it NEVER gets there.
Your motor will only draw as much air and fuel as it needs. That is why the Q junk has the two small main bores. 90% of the time you are driving on those two small ones sucking in 500 cfm.
If you happen to stomp on the gas, and if the rest of the system (intake manifold, valves, etc) can handle it, you may, but probably not, draw 650 tops for a brief second on a bone stock 350.
You can waste your money and time rebuilding an old Q junk or get a 650 Holley that is bolt on and will improve performance.
Fact of the matter is, on a bone stock car you can run a nice 600 and never ever have any issues. I ran one of these for years:
http://www.holley.com/0-80457S.asp
I only traded up to a Street Avenger 650 because of some performance upgrades.
Carter made Q junk licensed from GM. Rochester isn't a company, its the town the GM carb plant is in. Somehow they started calling them Rochesters.
A lot of folks live in a CFM fantasy world. Just because the the Q junk is allegedly capable of 750 CFM, it NEVER gets there.
Your motor will only draw as much air and fuel as it needs. That is why the Q junk has the two small main bores. 90% of the time you are driving on those two small ones sucking in 500 cfm.
If you happen to stomp on the gas, and if the rest of the system (intake manifold, valves, etc) can handle it, you may, but probably not, draw 650 tops for a brief second on a bone stock 350.
You can waste your money and time rebuilding an old Q junk or get a 650 Holley that is bolt on and will improve performance.
Fact of the matter is, on a bone stock car you can run a nice 600 and never ever have any issues. I ran one of these for years:
http://www.holley.com/0-80457S.asp
I only traded up to a Street Avenger 650 because of some performance upgrades.
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
pontnewynyddboy,
Do not throw your existing Q-Jet away. A good rebuild-able core can run $100, so if you don't get it rebuilt, stick it up on the shelf in a plastic bag.
I have used Holley carbs on my projects in the past and I probably will again. But, if your motor is stock right now and you are keeping it that way, I would have Lars rebuild your Q-Jet. If you are looking at rebuilding your engine and staying under 400hp, I would have Lars rebuild the Q-Jet for now, at least. You just need to let him know what all the engine/tranny/gear details are and he will set the carb up for you. His prices are very reasonable.
Do not throw your existing Q-Jet away. A good rebuild-able core can run $100, so if you don't get it rebuilt, stick it up on the shelf in a plastic bag.
I have used Holley carbs on my projects in the past and I probably will again. But, if your motor is stock right now and you are keeping it that way, I would have Lars rebuild your Q-Jet. If you are looking at rebuilding your engine and staying under 400hp, I would have Lars rebuild the Q-Jet for now, at least. You just need to let him know what all the engine/tranny/gear details are and he will set the carb up for you. His prices are very reasonable.