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  #1  
Old 02-12-2008, 08:26 AM
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Lindel Lindel is offline
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Carburetors in general, Holley's in particular; AKA Carb Tech

In light of the large number of questions concerning carbs lately, I've been doing some searching for tech info.

Holley's website contains a lot of information and tech advice for the browsing.

http://www.holley.com/TechService/Library.asp

This page in particular give links to info on cams, carbs, fuel injection, pistons, etc.

Edelbrock also has a tech site. http://www.edelbrock.com/automotive_...ll/index.shtml

Hope this helps some folks out.
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Last edited by Lindel : 02-12-2008 at 11:12 AM.
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Old 03-02-2008, 12:30 PM
Kristy Kristy is offline
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Thumbs up Thanks!

Thanks for the info! Very helpful!....Some of my parts are missing too!
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  #3  
Old 03-15-2008, 09:07 AM
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fulsizjeep fulsizjeep is offline
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Ristow's Excellent MC4350 Rebuild

http://www.ifsja.org/forums/vb/showthread.php?t=80329
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Old 04-14-2008, 09:14 PM
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carb. info.

.Q-jet great read. florida4x4.com/tech/quadrajet/qtune.pdf
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  #5  
Old 04-25-2008, 06:42 AM
kenny kustom kenny kustom is offline
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Whats the recomended fuel pressure for a mc 4350 ?
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  #6  
Old 04-25-2008, 01:56 PM
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5 to 7 psi would be more than adequate.
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Old 04-29-2008, 12:21 PM
kenny kustom kenny kustom is offline
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so my 7 psi is okay then ?
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Old 04-29-2008, 12:46 PM
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It's on the high side, but if it's been running ok I wouldn't worry about it.

Where are you measuring it at, that could make a difference.
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  #9  
Old 04-29-2008, 02:06 PM
kenny kustom kenny kustom is offline
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Quote:
Originally Posted by Lindel
Where are you measuring it at, that could make a difference.

At the carb. From my regulator. With the motor off.
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  #10  
Old 04-29-2008, 04:18 PM
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As long as you're not having flooding issues, then you're probably ok. If it starts flooding then you'll need to drop the pressure some.
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  #11  
Old 05-27-2008, 11:24 AM
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cajun_lad cajun_lad is offline
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What are the gains/losses of vacuum secondaries vs. mechanical?
The reason I ask is I rebuilt my Holley TA yesterday and my dad pointed out that it would be real easy to convert from vacuum to mechanical and went on to ramble about how he hated vacuum secondaries... blah, blah, blah. Should I take his advice, or leave well enough alone?
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Old 05-27-2008, 01:40 PM
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Lindel Lindel is offline
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Stick with vacuum secondaries. The reasoning is that they'll only open when the engine load demands more fuel/air. With mechanical secondaries, they'll open at WOT whether they need to or not.

Mechanical secondaries are almost exclusively a high performance item, not the best application for a 4x4.
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Old 05-28-2008, 10:52 AM
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I have a Holley Truck Avenger with electric choke that seems to run pretty good.

The problem I have is it will not idle down completely after it has been running a while. I can tap the throttle and it will idle down, but it will not do it on its own when I let off the gas, like at a stop light.

Any ideas what is causing this?
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  #14  
Old 05-31-2008, 04:04 AM
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HOOT HOOT is offline
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Guess I should look at the "Stickys" posts more often..

I've been beating my head for info on my Holley carb the last 2 days. No catalogs match my numbers.Today I go seek someone recommended by 3 of the 5 car parts stores I've been to in the last 2 days. I think I'll leave it with him and have him rebuild it.
I even seen one catalog that had the "specialty builds" listed by who they were for and what the did with them.ie.Driver's name/what style carb/jets/circle track racer... Still no numbers match. Did I get a carb that was heisted fom the plant piece by piece like that Johnny Cash song about the Caddy.

I'll try to remember to ask him about your idle problem.
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  #15  
Old 05-31-2008, 05:44 AM
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Lindel Lindel is offline
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toyjeep, Most likely the return spring isn't quite stiff enough, or you've got some binding in the throttle plate shaft.

Hoot, check the links I left in the first post, one should take you to where you can call the Holley tech line. Give them the info on your carb and see if they can't help you.
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Quote:
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Formerly of DFW/Gun Barrel City, TX - eventually to return...
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  #16  
Old 05-31-2008, 07:07 AM
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Quote:
Originally Posted by Lindel
toyjeep, Most likely the return spring isn't quite stiff enough, or you've got some binding in the throttle plate shaft.


Thx, I will check the linkage system and try a stiffer spring and see what happens.
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  #17  
Old 06-01-2008, 12:36 AM
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My carb now rests in the hands of a Holley god. He spent 1 minute scanning in his book and had the rebuild kit in his hands in under a minute. Then offered to rebuild it for me for $45. I'll let you know how it turns out.

ToyJeep,
I asked him about your idle and he suggested it may be a vacuum problem. He also said it could be the voltage on your electric choke. He was actually leaning towrds the choke voltage as the culprit.
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1980 J20 Utility bed truck. Factory cab and chassis truck. Many new mods for it but it will look all stock.
1985 J10 nothing special just a nice clean stock truck.
1977 Honcho "Blue" 401/400/quad. Under going major upgrades.."This is Not Your Fathers Honcho", it may not even be a Honcho anymore when done.
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  #18  
Old 06-01-2008, 07:34 AM
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toyjeep toyjeep is offline
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Quote:
Originally Posted by HOOT

ToyJeep,
I asked him about your idle and he suggested it may be a vacuum problem. He also said it could be the voltage on your electric choke. He was actually leaning towrds the choke voltage as the culprit.

Cool, thanks for the info. I will check that out as well.
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  #19  
Old 06-01-2008, 07:54 AM
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cajun_lad cajun_lad is offline
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ToyJeep, I had a similar problem with my choke. My dad (ex-mechanic and carb genius) tried adjusting the choke and couldn't get it dialed in so he bypassed it. When we rebuilt it last weekend, we noticed during reassembly that it was not assembled right from the beginning. There was no way possible that the choke would ever allow the flapper to close the way it was assembled. We took a closer look, and changed the way we assembled the choke lever (the red plastic looking piece) and voila, problem solved. I have not yet tried it cause the tranny is currently removed, but I will let you know the results as soon as it goes back together. I will also try to take some pics to show you what I am talking about, as I really don't know carb nomenclature.
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  #20  
Old 08-19-2008, 12:30 AM
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wickedwagon767 wickedwagon767 is offline
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I'm trying to decide wether or not I need to rebuild my MC 4350. I just bought the '78 Cherokee. It had to have a liberal spraying of started fluid and several attempts over a 20 minute period to get it started when I went to pick it up. Once it cranked it ran great. Cruised between 70 and 80 all the way home, about 35 miles.

I've been told the floats "get stuck" when older carbs sit for a while without being run. This one was a daily driver for a year, then was started periodically over six months until I bought it.

Any leads?
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