The Stovebolt.com Forums Home | Tech Tips | Gallery | FAQ | Events | Features | Search
Help is a click away!

VEHICLE
INFORMATION
KITS


at the

GM Heritage Center
All the details are here.

Searching the Site - a click away
click here to search
New here ??? Where to start?
Click on image for the lowdown. Where do I go around here?
====
Who's Online Now
2 members (ShopRag, LAROKE), 44 guests, and 4 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums66
Topics128,090
Posts1,056,347
Members48,442
Most Online14,466
Apr 26th, 2026
Step-by-step instructions for pictures in the forums
Brad Allen's photos

AD Chevy Trucks

Pictures galore
Over 6,000 pictures

Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips.

Check them out!

Lots of work on Brad's part ... pure enjoyment (and references) for you!

Big Thanks!

THANKS!

For helping keep this great
old truck web site
on the Internet for

over 30 years!

and not clogged down
with Ads!


Again, thanks!

Previous Thread
Next Thread
Print Thread
Joined: Nov 2002
Posts: 2,766
C
Carburetion specialist
Carburetion specialist
C Offline
Joined: Nov 2002
Posts: 2,766
There have been a number of threads about the replacement Chinese carburetors. While not a single barrel, here is an in-depth analysis of one of the Chinese knock-off Rochester Q-Jets by one of the most respected of all Q-Jet specialists:

Chinese Q-Jets

Those who believe in the tooth fairy, Santa Claus, or the cheap Chinese carburetors should read this article in its entirety!

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop
Joined: Dec 2018
Posts: 2,450
F
'Bolter
'Bolter
F Offline
Joined: Dec 2018
Posts: 2,450
carbking After years of Q-jet service whatever came in the door,if you put in a kit, a float,be sure base is flat,tune the pump and it will run ! Of course gotta have valves and a good cam seal the well plugs and so forth ! However glad that is over,now for hollys LOL LOL!!

Joined: Dec 2018
Posts: 2,450
F
'Bolter
'Bolter
F Offline
Joined: Dec 2018
Posts: 2,450
carbking Oh I forgot that trusshead screw that can get down it's throat drat !!

Joined: Feb 2004
Posts: 29,826
H
Kettle Custodian (pot stirrer)
Kettle Custodian (pot stirrer)
H Offline
Joined: Feb 2004
Posts: 29,826
Good info, Jon. BTW, thanks to our resident shade tree specialist for his words of wisdom!
LOL!
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
Joined: Jan 2014
Posts: 3,689
J
'Bolter
'Bolter
J Offline
Joined: Jan 2014
Posts: 3,689
Aren’t there enough rebuildable real Q Jets laying around to last us a few decades?

I don’t understand what the market need is here. There’s a bit more scarcity with the usable one barrels and I can understand the perceived need for the bad Zenith copies. Bad as they may be.


1951 3100
Joined: Nov 2002
Posts: 2,766
C
Carburetion specialist
Carburetion specialist
C Offline
Joined: Nov 2002
Posts: 2,766
JW - there are plenty of both available, one simply has to look. Sometimes instant gratification is not an option, one needs a wee bit of patience.

As to the Chinese knock-offs: if one has thousands of dollars of test equipment, and more thousands of dollars in spare parts, a lifetime of experience DESIGNING and repairing carburetors, and figures their time is worth absolutely NOTHING, then the Chinese knock-offs are cheap! wink

I linked Lars' post, as, along with Cliff Ruggles, they are the two most knowledgeble men of whom I am aware with Rochester Q-Jets.

Guessing someone that specializes in Zeniths could find about the same issues with the knock-offs.

But to each their own.

Jon


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop
Joined: Dec 2015
Posts: 491
D
Unconventional Thinker
Unconventional Thinker
D Offline
Joined: Dec 2015
Posts: 491
Thanks for sharing! I recently bought one of these thinking it was an Edelbrock Q-jet. I admittedly don't keep up on every single tiny detail of every manufacturer, so I was unaware that edelbrock hadn't made a q-jet in years. Theirs may have been better, but who knows. Anyhow, I bought a new M4MC for my '81 C20. It looked nice. I sent it back. I couldn't bring myself to install an inferior product on my truck. I like to work on it and have it run well, not tinker on it all the time to get it running well, and I had a feeling the chinesium c**p sitting atop my engine would be nothing but problems. So I opted to get a rebuilt Rochester instead. Reading the article I am glad I used my logic and sent it back. Just wish I had not bought it in the first place. But, we live and learn, well, most of us learn from our mistakes...lol... At least I got my money back sans restocking fee.


Shane

Shane's Toys...
2007 Forester XT Limited (2nd Owner)
1991 Cherokee Laredo (2nd Owner)
1981 Chevy 3/4 Ton Fleetside 8,600 Camper Special (3rd Owner)
1965 Chevy 3/4 Ton Fleetside (3rd Owner)
Joined: Nov 2002
Posts: 2,766
C
Carburetion specialist
Carburetion specialist
C Offline
Joined: Nov 2002
Posts: 2,766
DD - the edelbrock imitation Q-Jet wasn't a whole lot better, just like their imitation AFB's.

Jon.


Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop
Joined: Jan 2014
Posts: 3,689
J
'Bolter
'Bolter
J Offline
Joined: Jan 2014
Posts: 3,689
Originally Posted by carbking
JW - there are plenty of both available, one simply has to look. Sometimes instant gratification is not an option, one needs a wee bit of patience.

As to the Chinese knock-offs: if one has thousands of dollars of test equipment, and more thousands of dollars in spare parts, a lifetime of experience DESIGNING and repairing carburetors, and figures their time is worth absolutely NOTHING, then the Chinese knock-offs are cheap! wink

I linked Lars' post, as, along with Cliff Ruggles, they are the two most knowledgeble men of whom I am aware with Rochester Q-Jets.

Guessing someone that specializes in Zeniths could find about the same issues with the knock-offs.

But to each their own.

Jon

Yeah, I’m in no way defending the Chinese Zenith look-alike or suggesting that it’s impossible to find a good one barrel for your 235. But it’s easier for me to understand how someone could get tired of dealing with Rochester B’s, and impatient looking for a reasonably priced YF, Zenith, Stromberg etc. And out of that frustration take a chance on the offshore Zenith look-alike.

Q-Jets practically grow on trees by comparison. If one feels uncomfortable rebuilding oneself, it’s not hard to buy a rebuilt unit either. Or one from a running engine that is being removed for an LS swap, aftermarket EFI, etc.


1951 3100
Joined: Dec 2015
Posts: 491
D
Unconventional Thinker
Unconventional Thinker
D Offline
Joined: Dec 2015
Posts: 491
Originally Posted by carbking
DD - the edelbrock imitation Q-Jet wasn't a whole lot better, just like their imitation AFB's.

Jon.

I had a feeling they wouldn't be, as the engineers that built the q-jets for specific applications knew what each one needed to run properly, not a one-sized-fits-all. Or as Jerry says it, one-size-fits-none...lol... I just finished reading the "Jebby" article, didn't see it last night. Now getting back into the "Lars" article. Interesting reading thus far from each article.


Shane

Shane's Toys...
2007 Forester XT Limited (2nd Owner)
1991 Cherokee Laredo (2nd Owner)
1981 Chevy 3/4 Ton Fleetside 8,600 Camper Special (3rd Owner)
1965 Chevy 3/4 Ton Fleetside (3rd Owner)
Joined: Mar 2014
Posts: 4,504
J
Moderator, Electrical Bay
Moderator, Electrical Bay
J Offline
Joined: Mar 2014
Posts: 4,504
My favorite is this one (which to some might seem a comic book without words): https://tinyurl.com/2p8h4hre

A good example of "hope springs eternal"? Maybe. At any rate it makes me laugh every time I see it. A puzzling Communist copy of one of GMs most mediocre carburetors. Could they have made it worse? Hoo boy did they. Once you get past the charming two-tone air horn/float bowl, understand there are still only 4 screws holding it together (seem smaller than the original ones...maybe they used M4 screws). And if you look at the 6th image, you'll see one screw hasn't been tightened and is lacking a lock washer...but in their defense they did find some sort of a washer for the image. How many connections for the choke stove tube? I count 3. But with this carburetor, you may need all 3. Probably helps with power and gas mileage and reduces hair loss and cholesterol...and the vacuum loss from the 2 unused ones might make it run slightly leaner. But it does look interesting sitting on that Fenton manifold, lacking the auto-choke cover. Great marketing! And that throttle body? Aluminum? Magnesium? Lead? Pig iron? Remember there are only 17 shopping days until Christmas. Hurry and get yours. In fact I'd suggest buying all 12 the seller has available. One for every month, and I think you'll need all of them. The Rochester of The Month Club.


~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
Joined: Apr 2005
Posts: 2,098
R
'Bolter
'Bolter
R Offline
Joined: Apr 2005
Posts: 2,098
You can't rely on the ebay "rebuild's" either. My friend bought one for his 72 truck w/400 Big Block. It looked brand new, they machined off the stamping and assigned their own number. We installed it and messed with it for a half day and it would not run. The best we could do was a little above idle for a few minutes. We took it to a friend that has 50+ years rebuilding carburetors. He disassembled it and only thing he could find visually is that it had a Buick base but couldn't see any obvious reason it wouldn't work.
He ultimately obtained another Q-jet and it started right up and runs great. The ebay special is available if someone wants it for a door stop.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine
Joined: Jan 2014
Posts: 3,689
J
'Bolter
'Bolter
J Offline
Joined: Jan 2014
Posts: 3,689
Originally Posted by Jon G
My favorite is this one (which to some might seem a comic book without words): https://tinyurl.com/2p8h4hre

A good example of "hope springs eternal"? Maybe. At any rate it makes me laugh every time I see it. A puzzling Communist copy of one of GMs most mediocre carburetors. Could they have made it worse? Hoo boy did they. Once you get past the charming two-tone air horn/float bowl, understand there are still only 4 screws holding it together (seem smaller than the original ones...maybe they used M4 screws). And if you look at the 6th image, you'll see one screw hasn't been tightened and is lacking a lock washer...but in their defense they did find some sort of a washer for the image. How many connections for the choke stove tube? I count 3. But with this carburetor, you may need all 3. Probably helps with power and gas mileage and reduces hair loss and cholesterol...and the vacuum loss from the 2 unused ones might make it run slightly leaner. But it does look interesting sitting on that Fenton manifold, lacking the auto-choke cover. Great marketing! And that throttle body? Aluminum? Magnesium? Lead? Pig iron? Remember there are only 17 shopping days until Christmas. Hurry and get yours. In fact I'd suggest buying all 12 the seller has available. One for every month, and I think you'll need all of them. The Rochester of The Month Club.

Spent Uranium, I reckon. Nothing goes to waste.


1951 3100
Joined: Feb 2016
Posts: 1,990
7
'Bolter
'Bolter
7 Offline
Joined: Feb 2016
Posts: 1,990
My '78 Vette has the original Q-Jet, I put a kit in it several years ago and have zero issues with it even though I use pump gas with ethanal, and the car doesn't see many miles per year. I wouldn't even think of buying a new Chinese carb for anything. Great write-up. Oh, my '57 truck has a number's correct 2G on the 283, a kit in that 3-4 years ago and it works very well.


1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
Joined: Jan 2014
Posts: 3,689
J
'Bolter
'Bolter
J Offline
Joined: Jan 2014
Posts: 3,689
I think Q-Jets are pretty cool, overall.


1951 3100

Moderated by  Phak1, Woogeroo 

Link Copied to Clipboard
Home | FAQ | Gallery | Tech Tips | Events | Features | Search | Hoo-Ya Shop
Powered by UBB.threads™ PHP Forum Software 8.0.0