Which carb to buy?

I’m starting my restoration of my 1981 GMC High Sierra 4x4 with original 350 4 bolt main engine. I’m going to replace the carburetor but not not sure which to go with. I’m thinking Edelbrock but not sure which model? My truck will not be lifted or used off road. I’ll be driving it on country roads and some highway. I’m not looking to drag race it, I just want a great performing engine. Any recommendations?

I personally get along with the elderbrock, think mine are 1406. Though I'm itching to try one of their TSV 2 or 3's might look into them. If you go elderbrock, go ahead and buy a tuning kit for the carb. Plenty of stuff on you tube to see how to tune one, pretty easy.

Quadrajet would be my choice. I see you are from a pretty cold climate though, have you thought about going with an efi system?

...Everyone has their preferred carb, and it can vary heavily from person to person. Edelbrock has by far the easiest to maintain. The fact I, a complete newbie to rebuilding carbs could strip mine down, clean it, and reassemble it says a lot. Quadrajets, depending on how fancy you wanna go do have a nice factor, smaller primary, larger secondary, can help you a bit on fuel. I wont deny, the truck I have driven WITH a Quadrajet has given me a very healthy appreciation for the monstrosity they are to strip down and rebuild.

Personally, I like the 1405. But I am a sucker for a preference for manual choke. (plus it came free with the truck.) The 1406 is the same carb overall, but it is the electric choke version. I see no reason to go over a 600cfm Edelbrock with what I have learned so far. I havent learned nearly enough with their newer carb versions, Would need others to chime in on their efficiency rates.

You said restore
I say rebuild the correct Quadrajet.
It's a Faaaaaaaaar superior carb to an edelbrock / Carter piece of ****.

Or at least buy a Holley. SA670. .Best to rebuild your OE carb though. You won't find anything that will perform better. Imo.
Edelbrock carbs ******* suck.

I have luck with Rochesters if it's a decent core.A bad one is a very bad experience.Edelbrock in early years were carter.Later on lots of them were weber.I only had one and it did well enough on a 350 I built with a slightly over stock cam.But I've heard the hate on them but a little adjusting is all I've ever had to do.But I have to say I've had a few Rochesters and had to rebuild every single one.But I always liked the way they ran on a daily driver

I am currently using a Quadrajet and it now works well, but the truth is that getting a 40+ year old carb to work properly with a modified engine was not that simple. Quadrajets are infinitely tunable, but that is also why they are complicated to get properly adjusted. And when you rebuild one you are trying to fix the mistakes of past owners, which is also frustrating.

For a new carburetor I have found the Edelbrock AVS2 has gotten really good reviews, and it has several improvements over the old 1406. Almost every review talks about its crisp throttle response.

Bruce

Hands down HOLLEY, or you will be fiddling with it forever!!

75gmck25 said:

I am currently using a Quadrajet and it now works well, but the truth is that getting a 40+ year old carb to work properly with a modified engine was not that simple. Quadrajets are infinitely tunable, but that is also why they are complicated to get properly adjusted. And when you rebuild one you are trying to fix the mistakes of past owners, which is also frustrating.

For a new carburetor I have found the Edelbrock AVS2 has gotten really good reviews, and it has several improvements over the old 1406. Almost every review talks about its crisp throttle response.

Bruce

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Same thing I've heard. Way I understand it is instead of it letting the fuel in through a single tube, it has a ring with a bunch of little holes. supposed to help atomize the gas which makes alot of sense. That what your understanding Bruce?

CrazyArk said:

...Everyone has their preferred carb, and it can vary heavily from person to person. Edelbrock has by far the easiest to maintain. The fact I, a complete newbie to rebuilding carbs could strip mine down, clean it, and reassemble it says a lot. Quadrajets, depending on how fancy you wanna go do have a nice factor, smaller primary, larger secondary, can help you a bit on fuel. I wont deny, the truck I have driven WITH a Quadrajet has given me a very healthy appreciation for the monstrosity they are to strip down and rebuild.

Personally, I like the 1405. But I am a sucker for a preference for manual choke. (plus it came free with the truck.) The 1406 is the same carb overall, but it is the electric choke version. I see no reason to go over a 600cfm Edelbrock with what I have learned so far. I havent learned nearly enough with their newer carb versions, Would need others to chime in on their efficiency rates.

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More CFM is unfortunately equated with more power when there is a cut off where you need to do internal changes to your engine to need more than 600 generally. Race cars putting out 400hp or so with 107 or so octane gas be using 500cfm 2 barrels... its about how an engine is built and much more complex things than i am qualified to list.

But once you reach the higher CFM point, definitely a good point.

wanderinthru said:

Same thing I've heard. Way I understand it is instead of it letting the fuel in through a single tube, it has a ring with a bunch of little holes. supposed to help atomize the gas which makes alot of sense. That what your understanding Bruce?

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Power blast or something is a company that claims to make bolt on parts that do just that for 1406. i might try it for 40 bucks once my truck runs a consistent, good way that i can use as a before/after statement.

Edelbrocks are great and easy to tune regardless of what dude said above, I like all carbs and they are all pretty good. You need to take the time to tune it properly. Do yourself a favor and get and AFR gauge so you can easily dial in any fuel system you go with.

The quadrajet ran for decades, trouble free on new GM cars Vettes to farm trucks.A good quadrajet requires practically zero attention, if they were troublesome or inferior GM wouldn't have used them for so long.Next best thing to TBI IMHO. And I've had quadrajets, edelbrocks,Holley, webers. I've said it before and will say it again when people say they put x brand carb on and their truck ran so much better, they are comparing a 45 year old quadrajet that needs rebuilt to a brand new brand x. And anything other than stock is not restored, it's modified.

Paladin said:

Hands down HOLLEY, or you will be fiddling with it forever!!

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Agreed, its damm near impossible to rebuild one of those things and it run right, of course there's 30 guys on here that did it. My opinion of a quadrojet, and Ricko touched on it, they are fine when you buy new truck or car, but once it needs to be gone thru its best to throw it in the garbage and buy edel/holley. OP needs aluminum intake, headers, full duel exhaust, and a holley/edelbrock and he'll never have to touch it again. Also a stock 350 or even a cammed one w heads only needs 600cfm max. My last one, since I had em on the shelf, I went from 750 to 650 to a 550 and the latter found the sweet spot, it had heads and a cam as well....Roost

I got a 670 Street Avenger Holley I intend to run on my 2wd with a 350. I have even thought about getting a carb intake for an LS and still running the Holley.

As I mentioned, I'm using a Quadrajet and it currently works well. However, just to give you an idea of the configuration/tuning choices you have with a Quadrajet, these are some of the items I recorded for my carburetor. If I made a significant change in cam, heads or other parts I might have to go back through these settings to figure out what needed to be "tweaked." It is not a simple process.

Quadrajet 17080213 Q243 CPX
Idle tube .038
Idle down channel .055
Upper air bleed – in air horn, .052
Lower air bleed – .0625
Idle air – .110
Mixture screw hole – enlarged to .078
Jets #74
Primary rods - 50C
Secondary rods - DA
Secondary hangar - G
APT - 2 ½ turns out
Idle screws - 3 ¼ turns out
Power piston spring – red
Notched secondary flaps next to accelerating system holes
Secondary air valve ¼ turn tension
Accelerator pump - 2nd hole
Blue seal on accelerator pump
Float at 1/4”
2104 gasket

Base timing 15 BTDC
Mechanical adds 20 degrees by 2000 RPM
Manifold vacuum
15 degree vacuum advance

Bruce