Which carb???

[darush01]

I have a 72 c20 350 with a 4 spd, I'm on my 3rd quadrajet and I can't seem to get one to run like I want, they all ran fine before I swapped them to my truck, but I'm tired of quadrajunk, my motor is as stock as it was in 1972 aside from routine maintanence, I want a carb that I can bolt to my stock intake until I decide to upgrade, what I really want is a good reliable carb that will bolt right up use my stock accelerator cable and not empty my wallet completely, I'm on a tight budget and don't have alot of free time, so with that in mind what are my options? I know enough about working on these old trucks to do almost anything but in my situation I need to do as little as possible for a big result

[CC69Rat]

Id go with a ~600cfm Holley, not a big fan of the Edelbrocks, plus you mentioned you wanted out of the box reliability. Maybe I just haven't had good luck with the Edelbrock carbs, but the spacer, fuel pressure, fuel pump, etc. issues in your case might introduce less than 'out of the box' results.

Just my .02

I mean no disrespect, but I picked up on "They all ran fine till I swapped them to my truck" .. maybe the carb is not your problem (?) What's the truck doing?

[imjeff]

If all three ran fine until they were put on your truck...it's your truck! Look for a vacuum leak, fuel supply or ignition problem. Sounds like you swapped out the wrong component.

Jeff

[67 cst swb]

Originally Posted by darush01

...they all ran fine before I swapped them to my truck

Every engines needs are different. So taking a carb off of one engine and putting it on another, doesn't always mean the carb with run properly on the 2nd engine.
Think of an engine as an air pump. It pumps in air and out air. What a carburetor does is mixes fuel with that pumped in air to be burned in the combustion chamber to generate power to push down on the piston to put things in motion.
Now, although your engine is the same as any other 350cid engine as far as displacement goes, it may be very different in relation to... compression, flow in the heads, flow of intake, flow of exhaust, weight of vehicle, load put on vehicle by rear gear ratio, type of transmission, etc...
So, although it is possible to find that carb off another running vehicle that performs flawlessly on engine "A", the likeliness of it performing the same on engine "B" is slim. For all those 100's of people that were lucky enough to have this work for them, there are 1000's if not 10's of 1000's that it did not work out for.
I feel for ya, in a perfect world a 350 carb would be a 350 carb... or even better a small block Chevy carb would be a small block Chevy carb. But unfortunately there will be some tuning involved. Both Holley and Edelbrocks are very tuneable carburetors. But each is it own animal.
I HIGHLY recommend reading the provided tuning guide provided with Edelbrock carbs. I HIGHLY recommend reading the book on holleys printed by HPbooks (http://www.speedwaymotors.com/Holley...book,2776.html) its a very easy read and super educational on a ABC-123 basis.
Until you get a fuel injection system that adjusts itself by use of sensors and a computer. IT IS MY OPINION that any carb put on any vehicle will need some tuning in order to work properly.
As far as my thoughts on the carb brands?
In a nutshell, here it goes:
Rochester - good carb, very limited on available internal parts, limited as to available knowledge and people that know how to work on them
Holley (or similar, ie.. Barry Grant,etc...) Cannot be beat for performance, once you learn the theory and function of the carb they are easily to learn and easily tunable, parts are relatively available even at garage sales (lol) Only drawback is they are very easily effected by crappy fuel and contaminants in the fuel line, as in a grain of sand can hang open a needle and seat. And they typically need adjusting from time-to-time.
Edelbrock (or similar Carter) pretty good carb for driveability. Once you get the tune up "right" with use of the provided tuning guide from edelbrock, (which does not have the same jet & rod numbers as carter, so good luck) they are a pretty good carb. They are easily effected by too much fuel pressure and can take awhile to get that tune up "right"

Good luck in for carburetor searching

[imjeff]

Quadrajets have tons of available internal parts, everything can be adjusted and changed by removing the top and, judging by the hundreds of different applications they were available on (both small and big block) in the same CFM rating, they should work just fine on a stock 350. I don't know of a carb with as many secondary metering rod combos and their jets are available in many sizes as well. You didn't say what your truck was doing, but dumping hundreds into another carb seems a long shot to fix your problem. Why did you swap it out in the first place? Sounds like you had an issue, swapped the carb out to fix it, and it didn't. This is very common. People swap out carbs all the time due to other problems. I used to get given perfectly good "quadrajunk" carbs. Tell us what it's doing.

[68Gold/white]

The quadrajet CAN be the best carb, it will need to be tailored to your engine.

www.cliffshighperformance.com is the quadrajet answer man. He is VERY busy!!!

You will need your carb number. Send an email, he can tailor the parts needed for your specific carb, and for your specific vehicle. Get his book, it will get you where you need to go.

Send an email and be patient for a reply, believe me it's worth the wait!!!

[seattle gmc]

I just replaced my oringinal q-jet with a remaned q-jet from Roc Auto. 170$ after my core was returned. The thing has ran perferct out of the box so far, i haven't even adjusted the idle mixture screws yet.

[darush01]

Sorry guys, I was very tired when I posted this so I was vague, it's not really the carbs fault, it's me I messed up and put an 83 carb on a 72 and tried to swap all the linkages over from my old carb and wound up with the carb not functioning right the rear butterflies I'm pretty sure should open when I need them too but they don't and when I'm say going up a steep grade it sounds like its starving for air, plus it's running very rich, and the adjuster screws don't have heads they have little square ends, plus I know little about adjusting them and was told its a real pita, oh and with working parts I still can't get the choke to work, so its not the carb it's me I just want a functioning 4 barrel that will start without me sitting there pumping it a hundred times to start it, the factory carb worked fine until it started loping after it sat about a yr

[truckster]

Your best bet for an easy swap and great reliability is going to be a quality remanufactured Quadrajet. Check with Summit, JEGS, etc. The best rebuilder is Cliff Ruggles, but he has a really long waiting list.

[bpatrol]

my favorite carb is a quick fuel. they are test run and calibrated before being shipped.
a 600 qft with a choke would work great with little adjustment.
bpatrol

[darush01]

Another kinda unrelated ? When I shut the truck off it kicks back sometimes once sometimes alot, I was told it was timing but I'm pretty sure I've got that pretty close and when it does it I smell gas, what could cause that, the old truck hasn't had alot done to it in 40 years and I'm trying to build it into a nice driver but it's also my d/d so all the bugs have got to be worked out

[imjeff]

Originally Posted by darush01

Sorry guys, I was very tired when I posted this so I was vague, it's not really the carbs fault, it's me I messed up and put an 83 carb on a 72 and tried to swap all the linkages over from my old carb and wound up with the carb not functioning right the rear butterflies I'm pretty sure should open when I need them too but they don't and when I'm say going up a steep grade it sounds like its starving for air, plus it's running very rich, and the adjuster screws don't have heads they have little square ends, plus I know little about adjusting them and was told its a real pita, oh and with working parts I still can't get the choke to work, so its not the carb it's me I just want a functioning 4 barrel that will start without me sitting there pumping it a hundred times to start it, the factory carb worked fine until it started loping after it sat about a yr

What did the third quadrajet do?

[darush01]

First carb loped almost like I had a big cam, the second one just ran badly, the third does the job I just messed it up to where it can't get enough air and the choke sticks unless I just don't set it to close at all

[geezer#99]

It's time for pics of your carb!
Most goof- ups can be cured if we see what you got.

[darush01]

Ill take pics tomorrow when I have light

[truckster]

Originally Posted by darush01

Another kinda unrelated ? When I shut the truck off it kicks back sometimes once sometimes alot, I was told it was timing but I'm pretty sure I've got that pretty close and when it does it I smell gas, what could cause that, the old truck hasn't had alot done to it in 40 years and I'm trying to build it into a nice driver but it's also my d/d so all the bugs have got to be worked out

Not necessarily unrelated. Timing can affect how well your carburetor works; they both need to be tuned correctly. You need to get a timing light and make sure your timing advance is correct. If you're still running a points distributor, you need to make sure your gap and dwell angle are correct.

Another timing possibility is a very worn timing chain. That will throw of ignition timing as well as valve timing, which could lead to backfiring through the carb, which is what it sounds like you're describing.

[darush01]

Best description of what it's doing as far as timing is when I shut it off it still tries to run, it'll keep turning sometimes several rotations before it finally stops, the timing I can get figured out I think, ill just have to borrow a light, the points I'm gonna be honest I have no earthly clue what to do with them, I changed them and just messed with them til it ran the smoothest, my carb overall is running fine as long as I don't try to put the truck under strain then it messes up and I've got a 4 barrel that really only functions on 2, its my fault but I learn by doing but in this case I messed it all up and learned nothing

[truckster]

Originally Posted by darush01

Best description of what it's doing as far as timing is when I shut it off it still tries to run, it'll keep turning sometimes several rotations before it finally stops, the timing I can get figured out I think, ill just have to borrow a light, the points I'm gonna be honest I have no earthly clue what to do with them, I changed them and just messed with them til it ran the smoothest, my carb overall is running fine as long as I don't try to put the truck under strain then it messes up and I've got a 4 barrel that really only functions on 2, its my fault but I learn by doing but in this case I messed it all up and learned nothing

It sounds like you're really trying to learn. The best advice I can give you, even more important than what carb or distributor or anything else, is to find someone in your community who can help you and coach you.

[darush01]

I've got my dad when I'm back in town, he has been working on cars since the early 60's but he can only help me a limited bit bc of poor health, if I knew a fraction of what he does I'd fix anything without a problem, I mean he doesn't know it all but he knows these trucks, but when I got this whole mess started he was on life support and I was trying to drive 150 miles to get to the hospital so I just tried to swap carbs and go in a truck stop

[imjeff]

Originally Posted by darush01

Best description of what it's doing as far as timing is when I shut it off it still tries to run, it'll keep turning sometimes several rotations before it finally stops, the timing I can get figured out I think, ill just have to borrow a light, the points I'm gonna be honest I have no earthly clue what to do with them, I changed them and just messed with them til it ran the smoothest, my carb overall is running fine as long as I don't try to put the truck under strain then it messes up and I've got a 4 barrel that really only functions on 2, its my fault but I learn by doing but in this case I messed it all up and learned nothing

Get a cheap dwell gauge and set your dwell to 30 degrees (28-32). THEN set your timing with the vacuum unhooked and plugged. Your point dwell changes your timing by 2 degrees for every degree you change it. These are not adjustments to do by ear. Once your ignition is functioning correctly you can address your other issues.

[darush01]

Originally Posted by imjeff

Get a cheap dwell gauge and set your dwell to 30 degrees (28-32). THEN set your timing with the vacuum unhooked and plugged. Your point dwell changes your timing by 2 degrees for every degree you change it. These are not adjustments to do by ear. Once your ignition is functioning correctly you can address your other issues.

Ok random ? Where usually I know each area would be different but where can I get a dwell gauge

[geezer#99]

Autozone has them.
http://www.autozone.com/autozone/acc...er=122882_0_0_

[imjeff]

Originally Posted by darush01

Ok random ? Where usually I know each area would be different but where can I get a dwell gauge

You can get a decent dwell/tach/volt meter about anywhere for under $30. It's a must have along with a vacuum gauge.

[darush01]

Well autozone here just said they don't have any so I'm going to call the two other places in a 100 mile radius lol

[darush01]

Ok no one in about a 300 mile radius from me even understands what points are and I couldn't find it on the link for autozone can anyone look up a part number for me please