I’m sorry

[RichardJ]

>>OK, this thread has gone over the top for weird...<<


And, that is only half the fun. No one screamed out that the sky was falling. No one cried foul. No none insisted that the engine couldn't even be running much less than be running better than a Q-jet.

He has committed the offensive sin of using the ported vacuum port. Oh, the horror of it all.

This carb doesn't even appear to have the manifold vacuum port drilled.

Surely, a sin against the gear-head gods has been committed.

How's that for redirected topic?

[MikeB]

If someone hasn't mentioned it yet, the carb in the OP's picture is a Carter AFB. Each of those carbs was calibrated for a specific engine, in this case maybe an AMX 390.

Edelbrock sort of copied it and has probably sold at least tens of thousands over the years. They are rated at 500, 600, and 750CFM and have the fuel inlet on the passenger's side. Also, some of the AFBs had 3-step metering rods, whereas the Edelbrocks are 2-step.

I call TMI on myself!

[MikeB]

Originally Posted by Steeveedee

My original-to-the-truck QJet works just fine. I've rebuilt it ~four times in the last 40 years, three times while it belonged to my FiL. YMMV.

That is really cool!

[72c20customcamper]

Originally Posted by MikeB

If someone hasn't mentioned it yet, the carb in the OP's picture is a Carter AFB. Each of those carbs was calibrated for a specific engine, in this case maybe an AMX 390.

Edelbrock sort of copied it and has probably sold at least tens of thousands over the years. They are rated at 500, 600, and 750CFM and have the fuel inlet on the passenger's side. Also, some of the AFBs had 3-step metering rods, whereas the Edelbrocks are 2-step.

I call TMI on myself!

This is a 4759s made by Carter . 500 cfm made for the AMX with dual 4bbl setup . I got them and the manifold when my uncle was an AMC dealer

Edelbrock bought the rights to these and they were made along side of the Carter AFB on the same Webber carb line .So the really didn’t copy it

[RichardJ]

>>some of the AFBs had 3-step metering rods,<<

Actually, only the Carter AVS carbs used the 3-step rods. That includes the newer Edelbrock AVS carbs that are also the 2-step rod design.

>>Each of those carbs was calibrated for a specific engine,<<

Not as critical as some might assume. I have a 1970 383 Mopar Carter AVS on my 292 six and it works just fine with no jet changes. I did change the springs on the vacuum pistons above the rods. Its been on there about 17 years.

[special-K]

These guys did bad rebuilds, I don't care what their reputation "was". Never had an issue in my 50 years of running these trucks. I use a local benchwork rebuilder. Bolt on and go every time. The valve bodies or any number of parts not normally replaced in a routine rebuilt can wear out in over 50 years. A carb specialist could possibly just run a carb through not being as thorough as required for that particular carb. All carburetors go bad, have some kind of issue, and it doesn't happen to everyone. I've never had any carb rebuilt that didn't come back with pleasing results, any brand. I love the Carter square bores, but spread bore is the superior design by far except for WassOT race uses. I feel your pain, Mark. Your experience sucks

[MikeB]

Originally Posted by RichardJ

>>Each of those carbs was calibrated for a specific engine,<<

Not as critical as some might assume. I have a 1970 383 Mopar Carter AVS on my 292 six and it works just fine with no jet changes. I did change the springs on the vacuum pistons above the rods. Its been on there about 17 years.

I mentioned that because a while back I had been looking for a mid-60s 300hp/327 carb, and Jon at the Carburetor Shop (https://www.thecarburetorshop.com/History.htm asked me, "Which year?" As it turns out, the AFB model numbers changed over the years. Also there was one model # for auto trans, and another for manual, but that may have been nothing more than a trans kickdown lever. And, unlike today's Edelbrock versions, the carbs had fuel inlet locations and throttle linkage designed for specific engines, or at least specific manufacturers. And yes, Weber still makes them, but they're "universal" versions.

Had an AFB been used on a 292 six back then, you can bet it would have been a lot different than one meant for a Chrysler 383, or even a Chevy 327. But it's cool that yours has been working fine on the 292 all these years.

So, I'm not saying they won't work from car to car, all I'm saying is there tons of different model numbers for specific engines. Back in the day, I actually had one with a manifold from an Impala 327 that worked just fine on my 283 that had been bored to 292. The Impala's owner decided he needed a Z28 carb and manifold, as I recall.

Just found this:

CHEVROLET
1958 8 348 Carter AFB 2859 828
1959 8 348 Carter AFB 2897 828
1960 8 348 Carter AFB 3012 828
1961 8 348 Carter AFB 3221 831
1961 8 348 Carter AFB 3012 828
1961 8 409 Carter AFB 3270 829
1962 8 327 S/T Carter AFB 3269 567
1962 8 327 A/T Carter AFB 3310 567
1962 8 409(Front of 2) Carter AFB 3361 830
1962 8 409 (Rear of 2) Carter AFB 3362 830
1962 8 409 Carter AFB 3345 832
1963 8 327 300, 340 HP Carter AFB 3461 567
1963 8 327 300, 340 HP Carter AFB 3460 567
1963 8 409 Carter AFB 3499 829
1963 8 409 (Front of 2) Carter AFB 3361 830
1963 8 409 (Rear of 2) Carter AFB 3362 830
1964 8 327 S/T Carter AFB 3721 567
1964 8 327 A/T Carter AFB 3720 832
1964 8 409 Carter AFB 3783 833
1964 8 409 (Front of 2) Carter AFB 3361 830
1964 8 409 Carter AFB 3499 829
1964 8 409 (Rear of 2) Carter AFB 3804 830
1965 8 327 A/T Carter AFB 3720 832
1965 8 327 S/T Carter AFB 3721 567
1965 8 409 Carter AFB 3783 833
1965 8 409 (Front of 2) Carter AFB 3361 830
1965 8 409 (Rear of 2) Carter AFB 3804 830
1966 8 327 275 HP Carter AVS 4027 1442
1966 8 327 275 HP Carter AVS 4028 1442

Lots of AFB info here, from American Motors to Studebaker. Must be 200 P/Ns for Chrysler!
https://www.hemmings.com/partslocator/carburetors.html

I wonder if some of these "aftermarket" carbs are what Edelbrock Performer series carbs are based on?

9400 Aftermarket 400 CFM AFB
9410 Aftermarket 400 CFM AFB
9502 Aftermarket 500 CFMAFB choke less carb, with GM linkage
9511 Aftermarket 500 CFM AFB Chrysler linkage, for square-bore manifolds
9605 Aftermarket 600 CFM AFB manual choke carb, with GM linkage
9625 Aftermarket 625 CFM AFB
9626 Aftermarket 625 CFM AFB
9627 Aftermarket 625 CFM AFB
9635 Aftermarket 625 CFM AFB
9636 Aftermarket 625 CFM AFB
9637 Aftermarket 625 CFM AFB electric choke carb, with Ford linkage

For Aftermarket Competition Series:
CS 4758 500 cfm AFB
CS 4759 625 cfm AFB
CS 4760 750 cfm AFB
CS 4761 500 cfm AFB
CS 4762 750 cfm AFB

[chevmn]

Originally Posted by MikeB

I mentioned that because a while back I had been looking for a mid-60s 300hp/327 carb, and Jon at the Carburetor Shop (https://www.thecarburetorshop.com/History.htm asked me, "Which year?" As it turns out, the AFB model numbers changed over the years. Also there was one model # for auto trans, and another for manual, but that may have been nothing more than a trans kickdown lever. And, unlike today's Edelbrock versions, the carbs had fuel inlet locations and throttle linkage designed for specific engines, or at least specific manufacturers. And yes, Weber still makes them, but they're "universal" versions.

Had an AFB been used on a 292 six back then, you can bet it would have been a lot different than one meant for a Chrysler 383, or even a Chevy 327. But it's cool that yours has been working fine on the 292 all these years.

So, I'm not saying they won't work from car to car, all I'm saying is there tons of different model numbers for specific engines. Back in the day, I actually had one with a manifold from an Impala 327 that worked just fine on my 283 that had been bored to 292. The Impala's owner decided he needed a Z28 carb and manifold, as I recall.

Just found this:

CHEVROLET
1958 8 348 Carter AFB 2859 828
1959 8 348 Carter AFB 2897 828
1960 8 348 Carter AFB 3012 828
1961 8 348 Carter AFB 3221 831
1961 8 348 Carter AFB 3012 828
1961 8 409 Carter AFB 3270 829
1962 8 327 S/T Carter AFB 3269 567
1962 8 327 A/T Carter AFB 3310 567
1962 8 409(Front of 2) Carter AFB 3361 830
1962 8 409 (Rear of 2) Carter AFB 3362 830
1962 8 409 Carter AFB 3345 832
1963 8 327 300, 340 HP Carter AFB 3461 567
1963 8 327 300, 340 HP Carter AFB 3460 567
1963 8 409 Carter AFB 3499 829
1963 8 409 (Front of 2) Carter AFB 3361 830
1963 8 409 (Rear of 2) Carter AFB 3362 830
1964 8 327 S/T Carter AFB 3721 567
1964 8 327 A/T Carter AFB 3720 832
1964 8 409 Carter AFB 3783 833
1964 8 409 (Front of 2) Carter AFB 3361 830
1964 8 409 Carter AFB 3499 829
1964 8 409 (Rear of 2) Carter AFB 3804 830
1965 8 327 A/T Carter AFB 3720 832
1965 8 327 S/T Carter AFB 3721 567
1965 8 409 Carter AFB 3783 833
1965 8 409 (Front of 2) Carter AFB 3361 830
1965 8 409 (Rear of 2) Carter AFB 3804 830
1966 8 327 275 HP Carter AVS 4027 1442
1966 8 327 275 HP Carter AVS 4028 1442

Lots of AFB info here, from American Motors to Studebaker. Must be 200 P/Ns for Chrysler!
https://www.hemmings.com/partslocator/carburetors.html

I wonder if some of these "aftermarket" carbs are what Edelbrock Performer series carbs are based on?

9400 Aftermarket 400 CFM AFB
9410 Aftermarket 400 CFM AFB
9502 Aftermarket 500 CFMAFB choke less carb, with GM linkage
9511 Aftermarket 500 CFM AFB Chrysler linkage, for square-bore manifolds
9605 Aftermarket 600 CFM AFB manual choke carb, with GM linkage
9625 Aftermarket 625 CFM AFB
9626 Aftermarket 625 CFM AFB
9627 Aftermarket 625 CFM AFB
9635 Aftermarket 625 CFM AFB
9636 Aftermarket 625 CFM AFB
9637 Aftermarket 625 CFM AFB electric choke carb, with Ford linkage

For Aftermarket Competition Series:
CS 4758 500 cfm AFB
CS 4759 625 cfm AFB
CS 4760 750 cfm AFB
CS 4761 500 cfm AFB
CS 4762 750 cfm AFB

Wow... I wondered if Jon at the Carburetor Shop was still doing carbs/kits. I guess so. I used to live a few blocks from him, and he did all that in his basement. Had a 64 389 GTO with 3 carbs in his garage. The guy knows his carbs, and at one time had a ton of old stock kits, and had bought up most out of closed businesses.

[72c20customcamper]

The two rebuild shops are local . Both have been in business for years but like anything else time change . The ship that did my AFB also did the last Qjet . Now to be fair the guy that did my AFB was in his 80s and started the business in the 60s he had since passed and his grandson who worked there took over . Guess quality went down as now the shop is focused on new tuner stuff .

The other Qjet was done in new jersey . Again a long time shop I just got two bad ones . My 85 runs great with a Qjet .

[MikeB]

Originally Posted by chevmn

Wow... I wondered if Jon at the Carburetor Shop was still doing carbs/kits. I guess so. I used to live a few blocks from him, and he did all that in his basement. Had a 64 389 GTO with 3 carbs in his garage. The guy knows his carbs, and at one time had a ton of old stock kits, and had bought up most out of closed businesses.

There's some great stuff on his website. One of my favorites is his article on CFM ratings and how a 500 CFM AFB could be rated anywhere from 500 to 764, depending on the rating methodology. And how a 435 CFM Rochester 2bbl could be rated anywhere from 308 to 470.

Go down to "Carburetor Selection -- Single Carburetors" here, for some interesting info and insight.

https://www.thecarburetorshop.com/Carbshop_carbs.htm

And this statement by Jon makes me shake my head at Holley and Edelbrock for continually pushing square bore carbs on us. (OK, Edelbrocks are semi-spread bore.)

We have found that, for modern 8 cylinders of 300 CID or larger, almost without exception, a spread-bore carburetor (small primary, and large variable secondary) will perform best on the street.

[chevmn]

At the risk of going off topic, but still on the Q-Jet topic (maybe?), Many years ago, before I knew some of those issues with Q-Jets, I purchased a new Holley spreadbore q-jet replacement 450 cfm "economaster?" carb. I put that carb on a 400 small block with headers but bone stock otherwise with TH350 trans, and 3.31 gears in a mid 70's Chevelle (probably heaviest Chevelles every built). While some would argue that carb was too small for a heavy Chevelle with 400 in it, it was surprisingly responsive, and avg of low 20's in fuel mileage. Keep in mind this was at a time before fuel injection, or really any emission requirements, yet fuel prices were on the rise (or so we thought). That was the only Holley I have ever owned. I currently have a 72 C20 with factory (stock) 402, just rebuilt the factory Q-Jet and put on an aluminum Edelbrock high rise intake, and headers. Interested to see how it does. TH400, Dana 60 with 3.54 gearing. Should have put in a little more cam, but lets see what happens, and I can always do that during winter months if I am not happy.

[MikeB]

Originally Posted by chevmn

Many years ago, before I knew some of those issues with Q-Jets, I purchased a new Holley spreadbore q-jet replacement 450 cfm "economaster?" carb. I put that carb on a 400 small block with headers but bone stock otherwise with TH350 trans, and 3.31 gears in a mid 70's Chevelle (probably heaviest Chevelles every built). While some would argue that carb was too small for a heavy Chevelle with 400 in it, it was surprisingly responsive, and avg of low 20's in fuel mileage.
happens, and I can always do that during winter months if I am not happy.

I'm with you there! Yes, it was probably a 450 Economaster. In the early 90s, I bought one in a dusty box sitting on a shelf in the back of a parts store. It had a day-glow sale price sticker on it, and had been in the store for years. I put it on a bone stock truck 307 using a 327 Q-jet intake manifold that I bought for $10. Along with dual exhaust, the performance gains were much better than I had any right to expect. The truck was simply transformed -- performance and fuel mileage. Do you remember that the carb had mechanical secondaries?

Years earlier I had installed a Economizer 2-bbl carb on a 74 emissions-laden 350 Buick engine. It made the car run smoother at low-mid RPM and increased gas mileage by around 2 MPG. Bought that carb from a customer mine of who owned an auto parts store. He said it was a very popular item, and I can see why.

[body bolt]

Originally Posted by chevmn

At the risk of going off topic, but still on the Q-Jet topic (maybe?), Many years ago, before I knew some of those issues with Q-Jets, I purchased a new Holley spreadbore q-jet replacement 450 cfm "economaster?" carb. .

I run one of these on my truck and love it. The way it keeps pulling from 1st to 2nd with little pedal is very nice. Over time I've collected a pile of them. They're also simple to rebuild although the kits aren't cheap. The list numbers to look for are 7454, 7455, 7456 and all have mechanical secondaries. For our purposes those are all interchangeable.

['68OrangeSunshine]

Originally Posted by RichardJ

>>some of the AFBs had 3-step metering rods,<<

Actually, only the Carter AVS carbs used the 3-step rods. That includes the newer Edelbrock AVS carbs that are also the 2-step rod design.

>>Each of those carbs was calibrated for a specific engine,<<

Not as critical as some might assume. I have a 1970 383 Mopar Carter AVS on my 292 six and it works just fine with no jet changes. I did change the springs on the vacuum pistons above the rods. Its been on there about 17 years.

I found an AVS carb in a junkpile on a movie set. [Mid 1990s.] A set dressing prop from an abandoned 76 Unocal gas station location, supposedly in a post nuclear world. Bad guys were supposed to chase the hero around the gas station. He escapes by getting inside the big orange 76 ball, and rolling away inside it. Scene was cut from the script and never shot, after we built a whole fake gas station, in a parking lot. The carb would have been tossed out after wrap. So I gabbed it, as any Carter 4 barrel was interesting.

Turned out to be for a late '60s Mopar 440 from the numbers. Someone had played with it, however. The primary jets were in the secondary position and the other jets were missing. Also the secondary area had these perforated tubular probes, not annular rings. The jets were these deep cups. The 3-stage metering rods looked shot. [Worn and grooved.] New AVS 3-stage parts are inobtainable.
When Edelbrock came out with the Thunderer AVS, I bought some fresh Edl- parts for it, but nothing came of it. The project lost my interest when I couldn't find any information on AVS tuning.