1968 Corvette Q-jet
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 35
Likes: 1
1968 Corvette Q-jet
Guys, My 1968 with Automatic tranny Q-jet has no casting numbers and runs bad. Rather than just rebuilding it, I'm looking to buy a reman with casting numbers that match. Questions are:
1. How can I tell if my car has California emissions? Thought all 68 had smog pumps.
2. Corvettes and Camaros Q-jet have the same casting numbers, right?
3. Any other thing I should consider?
Thank you in advance.
1. How can I tell if my car has California emissions? Thought all 68 had smog pumps.
2. Corvettes and Camaros Q-jet have the same casting numbers, right?
3. Any other thing I should consider?
Thank you in advance.
Team Owner
Joined: Jun 2000
Posts: 38,923
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From: Southbound
Cruise-In II Veteran
Team Owner
Joined: Sep 2006
Posts: 31,274
Likes: 4,366
From: Westminster Maryland
Hi t,
A 68 327/300, automatic car had a #7028208 DB carburetor installed on it originally.
A 68 427/390, automatic car had a #7020216 FF carburetor installed on it originally.
They both had date codes on them too.
Regards,
Alan
A 68 327/300, automatic car had a #7028208 DB carburetor installed on it originally.
A 68 427/390, automatic car had a #7020216 FF carburetor installed on it originally.
They both had date codes on them too.
Regards,
Alan
Last edited by Alan 71; Mar 25, 2016 at 10:13 AM.
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 35
Likes: 1
I've read some bad stories, but would like to keep it original as possible. Is it the carb itself horrible or the average person that don't know how to rebuild them?
I'm looking at one with 7028212. Chevy used 0,1, and 2, for the 6th digit.
Does anyone really care if the carb is correct, for matching numbers car? If not, what carb would y'all recommend?
I'm looking at one with 7028212. Chevy used 0,1, and 2, for the 6th digit.
Does anyone really care if the carb is correct, for matching numbers car? If not, what carb would y'all recommend?
Last edited by txnese; Mar 25, 2016 at 10:36 AM.
Drifting
Joined: Oct 2005
Posts: 1,615
Likes: 150
From: Forth Worth TX
If you want a "matching" numbers car, then you need to find one of the carbs that Alan 71 mentioned above, based on which engine you have.
If you don't care about a "matching" numbers car, then just about any Quadrajet (4MV) will work.
A 7028212 was originally installed on a 1968 Camaro with a 350/295hp Power Glide.
If you don't care about a "matching" numbers car, then just about any Quadrajet (4MV) will work.
A 7028212 was originally installed on a 1968 Camaro with a 350/295hp Power Glide.
Last edited by Revi; Mar 25, 2016 at 10:54 AM.
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
If you buy a remanufactured quadrajet, you might get a fuel bowl with the casting numbers you want––but you'll also get a mixed bag of other parts that on the whole might make the carburetor a total loss. Quadrajets were built to be application specific, and remanufactured units are not (a fuel bowl from a Corvette, an airhorn from a C10, etc.). This is what makes them untunable. The worst possible option is often a remanufactured unit.
Hit the internet for a rebuildable core and go from there, they are easy to rebuild. If you really want the correct carb, try posting in the for sale / wanted section and be patient––and rebuild a core in the meantime.
Hit the internet for a rebuildable core and go from there, they are easy to rebuild. If you really want the correct carb, try posting in the for sale / wanted section and be patient––and rebuild a core in the meantime.
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Drifting
Joined: Oct 2005
Posts: 1,615
Likes: 150
From: Forth Worth TX
When I called Phil his suggestion was for me to unplug my vacuum advance to the distributor because that was tricking the car into running to rich.
I then sent the re-manufactured carb to Lars, where I got a list of all of the things wrong with it. He said it was a challenge to get it corrected.
That's my $.02 cents.
Racer
Joined: Aug 2013
Posts: 264
Likes: 58
From: Virginia
I've read some bad stories, but would like to keep it original as possible. Is it the carb itself horrible or the average person that don't know how to rebuild them?
I'm looking at one with 7028212. Chevy used 0,1, and 2, for the 6th digit.
Does anyone really care if the carb is correct, for matching numbers car? If not, what carb would y'all recommend?
I'm looking at one with 7028212. Chevy used 0,1, and 2, for the 6th digit.
Does anyone really care if the carb is correct, for matching numbers car? If not, what carb would y'all recommend?
If you do rebuild one on your own, you can still end up with problems, as you are definitely not the first person to have taken that carb apart, and have no idea what anyone else has done to it. Wrong screws, warped sections from over-tightening, "drilled" parts, bent parts, worn parts, wrong tubes, damaged parts, wrong springs, floats, cracks, you name it! Study up on it first. Get smart on it before you buy a core. Lots of good gouge on the forum, and other places. Good book by Cliff Ruggles. And of course, Lars' posts.
This was the carb I had when I bought the car. Engine fire waiting to happen.
.
Just how does this fill with fuel???
Leaks everywhere.
Leaking mess, fire waiting to happen!
Even after I used a quality rebuild kit, I found it was warped, and had a coulpe cracks, and leaked at fuel inlet, where someone had already installed a helicoil. Trash.
Good luck
Racer
Joined: Aug 2013
Posts: 264
Likes: 58
From: Virginia
My experience with Phil was for a 70 L-46 as well. The carb was so out of tune/rich the fuel cloud behind the car could have been lit with a lighter.
When I called Phil his suggestion was for me to unplug my vacuum advance to the distributor because that was tricking the car into running to rich.
I then sent the re-manufactured carb to Lars, where I got a list of all of the things wrong with it. He said it was a challenge to get it corrected.
That's my $.02 cents.
When I called Phil his suggestion was for me to unplug my vacuum advance to the distributor because that was tricking the car into running to rich.
I then sent the re-manufactured carb to Lars, where I got a list of all of the things wrong with it. He said it was a challenge to get it corrected.
That's my $.02 cents.
What did he find wrong with it?
I only spent about 10 minutes after I fired it up with the light and vacuum guage. that was almost 2 years ago. I think Danny? was the guy that worked on my replacement carb at Phil's shop. And it took him an extra day and a half to get it done. I am hoping now that he had to source the appropriate parts to set it up correctly, since it seemed practically suitable right out of the box. I specifically told them to set it up for a '70 L-46 specs 7040207 qjet.
Is yours working ok now? or did you have to get another one?
That unplug vacuum line advice is a little wacky!
Last edited by CV62Air; Mar 26, 2016 at 10:56 AM. Reason: add content
Thread Starter
Intermediate
Joined: Oct 2015
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While I take my time looking for a matching replacement. I may get this one rebuilt or install an aftermarket, both options are about $200-$300. This way, I get to enjoy the car, instead of letting her sit in the garage. What's a good aftermarket that's easy to install without needing much modification. I'm not racing or anything, just wanting to be able to drive it on the weekends. I was thinking of Holley 1850. I have no real experience with carburetors. Any advice? Thanks.
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
Lars
Drifting
Joined: May 2012
Posts: 1,353
Likes: 44
From: Calgary Alberta
While I take my time looking for a matching replacement. I may get this one rebuilt or install an aftermarket, both options are about $200-$300. This way, I get to enjoy the car, instead of letting her sit in the garage. What's a good aftermarket that's easy to install without needing much modification. I'm not racing or anything, just wanting to be able to drive it on the weekends. I was thinking of Holley 1850. I have no real experience with carburetors. Any advice? Thanks.
Get a good quadrajet core and rebuild the thing with a quality kit. It will be relatively cheap and serviceable.
Not all of them have been hacked up inside.