Still runnin' a Q-Jet? Seen the Oct. CT mag? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

ChevLoRay · 08-20-2009, 09:31 PM

Pages 31-40 of the October Classic Trucks magazine has a nice in-depth article about the Q-Jet, by Moses Ludel. Nice pics and great info. I was impressed. I know there are a lot of other pubs with more data, but for the uninformed, this is a good introduction.

Jim_PA · 08-20-2009, 09:40 PM

You can't go wrong with a Q-jet

KEL · 08-21-2009, 07:12 AM

couldn't find the article on line
got a link ?

prostreetC-10 · 08-21-2009, 07:59 AM

Quote:

Originally Posted by Jim_PA

You can't go wrong with a Q-jet

Jim_PA · 08-21-2009, 08:33 AM

Quote:

Originally Posted by prostreetC-10

**Stocker** · 08-21-2009, 08:44 AM

I really have no complaints about my Q-jet. It was rebuilt many years ago and all is still good. I have been told they are better at severe angles (off road) than many other carbs.....

**WorkinLonghorn** · 08-21-2009, 09:19 AM

Here's another article from Classic Truck by Moses Ludel about tuning a Q-jet (and others);

http://www.classictrucks.com/tech/09...ics/index.html

C20-67_N_MO · 08-22-2009, 10:27 AM

Quote:

Originally Posted by prostreetC-10

x10

BarryB · 08-21-2009, 08:02 AM

I actually like a Q-jet, when there built correctly. Plus they can be tuned to get good MPG. I don't get CT anymore, So if somebody finds a link to it online. please post it?

69GMCLonghorn · 08-21-2009, 09:29 AM

On the primaries, I always found my Holly outperformed the Q-jet, but there's more of a kick when you open up the secondaries on a Q-jet than my Holly.

Jim_PA · 08-21-2009, 09:44 AM

Quote:

Originally Posted by 69GMCLonghorn

On the primaries, I always found my Holly outperformed the Q-jet, but there's more of a kick when you open up the secondaries on a Q-jet than my Holly.

Set-up and tuned properly, you shouldn't feel a difference between the primaries and secondaries. It was probably running lean on the primary side.

ChevLoRay · 08-21-2009, 10:31 AM

That link is the right article. Pix are larger in the mag, but this is good.

One thing I found after I installed my Edelbrock 1901 Q-Jet was that it ran much leaner than the Edelbrock 1405 that was on my truck when I bought it. In fact, I had to add a heat shield to the starter solenoid, and I also saw my gas-fouled plug problem go away. Starts are "NOW" and no flooding issues.

Bears63 · 08-21-2009, 09:29 AM

I do love the Q-jet. When built and tuned properly you just can't beat them in my book.

69GMCLonghorn · 08-21-2009, 10:50 AM

I'll still take a good old HOLLY over a Q-jet any day! (I know, I know... there goes that can o' worms again!)

Jim_PA · 08-21-2009, 11:23 AM

Quote:

Originally Posted by 69GMCLonghorn

I'll still take a good old HOLLY over a Q-jet any day! (I know, I know... there goes that can o' worms again!)

It's OK -- all you are missing out on is driveability, performance, and economy

69GMCLonghorn · 08-21-2009, 12:29 PM

Quote:

Originally Posted by Jim_PA

It's OK -- all you are missing out on is driveability, performance, and economy

Ok, now ya done it! After I tuned my Holly, it ran so well, the choke was removed completely (and no it wasn't running fat), gas mileage improved, power is great... I just have to keep a fire extinguisher handy for WHEN it starts to leak!! HAHAHAHA!!!!

Jim_PA · 08-21-2009, 12:54 PM

Quote:

Originally Posted by 69GMCLonghorn

Ok, now ya done it! After I tuned my Holly, it ran so well, the choke was removed completely (and no it wasn't running fat), gas mileage improved, power is great... I just have to keep a fire extinguisher handy for WHEN it starts to leak!! HAHAHAHA!!!!

I don't have a choke either! It saves me at least 3 ounces of weight.

prostreetC-10 · 08-21-2009, 02:32 PM

Quote:

Originally Posted by 69GMCLonghorn

Ok, now ya done it! After I tuned my Holly, it ran so well, the choke was removed completely (and no it wasn't running fat), gas mileage improved, power is great... I just have to keep a fire extinguisher handy for WHEN it starts to leak!! HAHAHAHA!!!!

Oaky 69GMCLonghorn......you and I need to team up to fight the forces of evil when it comes to the Q-jet villians and their leader PA Jim! I have a small Holley business/hobby I run out of my garage and have gotten to know them quite well. I've been doing a lot of the 750 HP's and they've been working out great. Here is a completed one. Granted, it's not nearly as pretty as a Q-jet, which is why I should be running 2 of them instead of my Holleys (LOL), but what are you gunna do.

Jim_PA · 08-21-2009, 11:26 PM

Quote:

Originally Posted by prostreetC-10

Oaky 69GMCLonghorn......you and I need to team up to fight the forces of evil when it comes to the Q-jet villians and their leader PA Jim! I have a small Holley business/hobby I run out of my garage and have gotten to know them quite well. I've been doing a lot of the 750 HP's and they've been working out great. Here is a completed one. Granted, it's not nearly as pretty as a Q-jet, which is why I should be running 2 of them instead of my Holleys (LOL), but what are you gunna do.

Behold, the 800 CFM quadrajet (and please excuse my ghetto throttle linkage/return spring setup

). The second most feared carburetor in their nearly 20 years of production. The 800's were on many trucks in the late 70's. Second only to the early 70's Pontiac Super Duty 850 CFM quadrajets. If you come across a 71 or 72 Pontiac Super Duty Quadrajet, and throw it in the trash, you probably just threw $800-$1000 away.

I think I got this one for free. I recall offering a challenge to you -- Holley vs Qjet at the track, and I believe I never got a response

So... How do you identify an 800 CFM quadrajet??? Look inside the primaries, and notice the "hump" in the bore of the primaries right where the venturi booster meets the primary bore. Yeah, I know myself and just about everyone else doesn't need an 800 CFM carb, but the benefit to these is a stornger primary side (not as much of a need to crack open the massive secondaries...)

A 750 CFM quadrajet will not have this hump, it'll be smooth all the way around. Nothing at all wrong with the 750's either, WOT performance should be equal, unless you actually need 800 CFM's for your engine's breathing requirements (highly unlikely...)

If you have an 800 CFM quadrajet, give it to me. I'll gladly pay you for every one

mclairmo · 08-21-2009, 01:25 PM

You don't need a choke, right? It just impedes airflow.

**WorkinLonghorn** · 08-21-2009, 01:32 PM

I don't need one because,well,I live in Southern California. Haven't had a choke since hmmmmm, a LONG time ago!

**WorkinLonghorn** · 08-21-2009, 01:35 PM

But I do like my Q-jet. Runs good and lean on primaries,good and stong on secondaries,no problems ever (10years since I went through it).

Jim_PA · 08-21-2009, 02:02 PM

Quote:

Originally Posted by mclairmo

You don't need a choke, right? It just impedes airflow.

If you modify it, most likely not, but from the factory, the idle circuits are pretty lean, so a choke is almost mandatory.

I left the high idle system in place for cold winter days, just removed the choke flap itself.

69GMCLonghorn · 08-21-2009, 04:42 PM

Ok, I really wasn't looking to open the flood gates on the debate again... BUT IT IS FUN!!! HAHAHA

I'm a big fan of Holley's, I've been running them for over 20 years on my old vehicles, but I can't say much bad about the Q's... Think about it: Someone was good enough to have created a carburetor that was approved FOR YEARS for use on BIG BLOCKS with the California Air Resources Board!! Talk about an accomplishment!

BIG69GMC · 08-21-2009, 05:08 PM

talking about Q-jet, where can i find one? I've started looking and cant find one for my '69 , looked into summit, still couldnt find one. i found one for my '73 monte w/350cid, not sure if they would be interchangeable? like if i bought one for my monte and ran it on the truck?

08-20-2009, 09:31 PM	#1
ChevLoRay Old Skool Club Join Date: Jun 2001 Location: Benton, AR "The Heart of Arkansas" Posts: 10,880	Still runnin' a Q-Jet? Seen the Oct. CT mag? Pages 31-40 of the October Classic Trucks magazine has a nice in-depth article about the Q-Jet, by Moses Ludel. Nice pics and great info. I was impressed. I know there are a lot of other pubs with more data, but for the uninformed, this is a good introduction. __________________ Member Nr. 2770 '96 GMC Sportside; 4.3/SLT - Daily driven....constantly needs washed. '69 C-10 SWB; 350/TH400 - in limbo The older I get, the better I was.

08-20-2009, 09:40 PM	#2
Jim_PA Registered User Join Date: May 2005 Location: PA Posts: 2,696	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? You can't go wrong with a Q-jet

08-21-2009, 07:12 AM	#3
KEL 72 GMC Join Date: Feb 2008 Location: Wells, Maine Posts: 535	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? couldn't find the article on line got a link ?

08-21-2009, 08:44 AM	#6
Stocker 20' Daredevil (Ret) Join Date: May 2003 Location: Jefferson State Posts: 13,751	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? I really have no complaints about my Q-jet. It was rebuilt many years ago and all is still good. I have been told they are better at severe angles (off road) than many other carbs..... __________________ - Mike - 1972 K20 LWB 350/350/205 RIP El Jay Last edited by Stocker; 08-21-2009 at 08:44 AM.

08-21-2009, 09:19 AM	#7
WorkinLonghorn Senior Member Join Date: Dec 2006 Location: Studio City, Calif. Posts: 2,886	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? Here's another article from Classic Truck by Moses Ludel about tuning a Q-jet (and others); http://www.classictrucks.com/tech/09...ics/index.html __________________ '69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, stereo speakers, 2nd owner, Work-Truck supreme.

08-21-2009, 08:02 AM	#9
BarryB Senior Member Join Date: Jul 2006 Location: Blountville, Tn. Posts: 3,904	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? I actually like a Q-jet, when there built correctly. Plus they can be tuned to get good MPG. I don't get CT anymore, So if somebody finds a link to it online. please post it? __________________ We could learn a lot from crayons... Some are sharp; some are pretty;and some are dull. Some have weird names; and all are different colours;but they all have to live in the same box. You may be only one person in the world, But you may also be the world to one person. * Some mistakes are too much fun to only make once. Two rules in life. 1. Never sweat the small stuff! 2. Everything is small stuff!

08-21-2009, 09:29 AM	#10
69GMCLonghorn Registered User Join Date: Dec 2006 Location: Porter Ranch, CA Posts: 978	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? On the primaries, I always found my Holly outperformed the Q-jet, but there's more of a kick when you open up the secondaries on a Q-jet than my Holly.

08-21-2009, 10:31 AM	#12
ChevLoRay Old Skool Club Join Date: Jun 2001 Location: Benton, AR "The Heart of Arkansas" Posts: 10,880	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? That link is the right article. Pix are larger in the mag, but this is good. One thing I found after I installed my Edelbrock 1901 Q-Jet was that it ran much leaner than the Edelbrock 1405 that was on my truck when I bought it. In fact, I had to add a heat shield to the starter solenoid, and I also saw my gas-fouled plug problem go away. Starts are "NOW" and no flooding issues. __________________ Member Nr. 2770 '96 GMC Sportside; 4.3/SLT - Daily driven....constantly needs washed. '69 C-10 SWB; 350/TH400 - in limbo The older I get, the better I was.

08-21-2009, 09:29 AM	#13
Bears63 ...just another truck junkie.. Join Date: May 2009 Location: Watertown, SD Posts: 698	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? I do love the Q-jet. When built and tuned properly you just can't beat them in my book. __________________ Mike "Bear" Shea

08-21-2009, 10:50 AM	#14
69GMCLonghorn Registered User Join Date: Dec 2006 Location: Porter Ranch, CA Posts: 978	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? I'll still take a good old HOLLY over a Q-jet any day! (I know, I know... there goes that can o' worms again!)

08-21-2009, 01:25 PM	#20
mclairmo Registered User Join Date: Jan 2006 Location: Take Off Posts: 1,908	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? You don't need a choke, right? It just impedes airflow.

08-21-2009, 01:32 PM	#21
WorkinLonghorn Senior Member Join Date: Dec 2006 Location: Studio City, Calif. Posts: 2,886	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? I don't need one because,well,I live in Southern California. Haven't had a choke since hmmmmm, a LONG time ago! __________________ '69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, stereo speakers, 2nd owner, Work-Truck supreme.

08-21-2009, 01:35 PM	#22
WorkinLonghorn Senior Member Join Date: Dec 2006 Location: Studio City, Calif. Posts: 2,886	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? But I do like my Q-jet. Runs good and lean on primaries,good and stong on secondaries,no problems ever (10years since I went through it). __________________ '69 GMC C2500 Custom Camper, 8 1/2' bed, New GM 350, NP 435 Close Ratio 4spd. Trans., 3.73 Dana-60 open.Camper and Trailer wiring, PS, PB, AC, tach , three gas tanks, stereo speakers, 2nd owner, Work-Truck supreme.

08-21-2009, 04:42 PM	#24
69GMCLonghorn Registered User Join Date: Dec 2006 Location: Porter Ranch, CA Posts: 978	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? Ok, I really wasn't looking to open the flood gates on the debate again... BUT IT IS FUN!!! HAHAHA I'm a big fan of Holley's, I've been running them for over 20 years on my old vehicles, but I can't say much bad about the Q's... Think about it: Someone was good enough to have created a carburetor that was approved FOR YEARS for use on BIG BLOCKS with the California Air Resources Board!! Talk about an accomplishment!

08-21-2009, 05:08 PM	#25
BIG69GMC Registered User Join Date: Jul 2009 Location: Albuquerque, NM Posts: 101	Re: Still runnin' a Q-Jet? Seen the Oct. CT mag? talking about Q-jet, where can i find one? I've started looking and cant find one for my '69 , looked into summit, still couldnt find one. i found one for my '73 monte w/350cid, not sure if they would be interchangeable? like if i bought one for my monte and ran it on the truck?



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