Carb knowledge requested?...

Beaumont4008 · Uber Guru

Carb knowledge requested?...

4SPEED427 · A Poncho Legend!

03cts sport wrote:

Carl Stevenson wrote:
Well, after your beauty rest (come spring, I guess) if you can get the casting number of there I bet we will solve this mystery pretty quick.

And please don't do like so many guys who I've tried to help identify a Chevy intake. They come back with the number 18436572!!!! (The engine firing order for those who don't know!)

Actually, likely underneath the coil you will have the date code. In your case, if it's a June car, it will likely be something like E 20 6 or E 20 66 for May 20 1966 for example.

Haaa, it'll take longer than spring to sort out what I've got going!
Re the firing order, thanks for saving me the embarassment! So is it simply a date code or am I looking for either 3931575 or 3888886 marked somewhere visable?
thx

I'd say copy everything but 18436572! And yes, the 7 digit number will be visible elsewhere.

-- Edited by Carl Stevenson on Monday 4th of January 2010 01:26:16 AM

03cts sport · Uber Guru

I'll try to get it tomorrow.
Night night.

-- Edited by 03cts sport on Monday 4th of January 2010 02:44:58 PM

4SPEED427 · A Poncho Legend!

Good night. Thanks for helping pass the evening!

rabbit64cs · Canadian Poncho Superstar!

from the carburetor shops we site...

Carter built quadrajets: Carter Carburetor Company of St. Louis produced millions of quadrajets under license from GM from 1966 through 1979. These carburetors carry the exact same identification as their Rochester counterparts, and parts are directly interchangeable. Carter also produced "aftermarket" replacement quadrajets, which will be identified by the traditional Carter part number (4 digits, followed by the letter "S"). An example of this numbering system would be 4675S, which is identical except for the number to 7028262.

http://www.carburetor.ca/carbs/tech/Carter/AFB-AVS-index.html

Carter AVS carbs appeared in 1966 on the 275 HP version of the Chevrolet 327, but were never again used on Chevies after that. AVS carbs were found mostly on Mopar applications from 1968-1971. The most sought-after AVS carbs are the 800 cfm models found on 440 CID motors.

Recently, Edelbrock has been marketing the Thunder Series AVS carburetor, again reproduced by Weber USA.

Carter did not build a performance version of the AVS after OEM production in the 1971 model year.

-- Edited by rabbit64cs on Monday 4th of January 2010 01:41:07 PM

cheetah 427 · Poncho Master!

i have been looking at carbs and the one on the 66 sd 275 hp car was a carter for sure, the gas inlet was on the back on the passenger side, this was a untouched 66 275 hp sd car .

03cts sport · Uber Guru

Here's a manifold shot that my brother took....

Beaumont4008 · Uber Guru

Shows in my book as carter or holley appliation.

4SPEED427 · A Poncho Legend!

Yup. I have that indentical intake.

Guess you are on the hunt for a Carter AVS is my guess.

It may have been a Holley but until someone proves me wrong, I will stick my neck out and say the Canadian models only used Carter or Rochester.

4SPEED427 · A Poncho Legend!

It's important to remember that most of the information printed is Chevelle and it's printed for the US models.

4SPEED427 · A Poncho Legend!

Most likely the casting date is in the shadow under the coil.

Beaumont4008 · Uber Guru

I agree with you Carl, I just can not see them using a Holley. Good thing he did not purchase a Quadrajet carb as would not fit on this manifold. Just wondering what carb is on there now ?

rabbit64cs · Canadian Poncho Superstar!

I pulled down that AVS I squirelled away, wire brushed it off,, It is 4401S J7 , intended for a 68 Chrylser 383. I was clueless that chevy ran them...so now I know !!

4SPEED427 · A Poncho Legend!

Doesn't that base look like a Carter AVS, now that you mention it?

rabbit64cs · Canadian Poncho Superstar!

yes it does , or an AFB, the 1/4 plug in the vacuum port is a telling sign.

So,, does he have the correct carb already????

03cts sport · Uber Guru

Man, you guys are good. It currently is indeed a replacement Carter 9625 (see attached).

03cts sport · Uber Guru

rabbit64cs wrote:

So,, does he have the correct carb already????

The original was swapped back in '87. I have no idea what it was...

03cts sport · Uber Guru

03cts sport wrote:

Man, you guys are good. It currently is indeed a replacement Carter 9625 (see attached).

Are there major differences between the Carter 9625 and the Carter AVS?...
thx

rabbit64cs · Canadian Poncho Superstar!

here is an explanation of the differences...mostly how the secondaries work

Carter AFB for Studebaker

The Carter AFB (Aluminum Four Barrel) was the second four barrel carburetor produced by Carter, after the WCFB. AFB's appeared in 1957 and were used as original equipment on most makes of car at one time or another up to 1971. The last notable OEM application was as a dual-quad setup on 1971 Dodge 426 Hemi engines.

Interestingly, some Ford AFB's weren't made of aluminum at all, and were in fact cast out of zinc.

Carter AFB's were produced as the Carter Performance Series carbs until 1998. They are currently available as Edelbrock AFB carbs, which are produced by Weber USA. Most parts, including tuning parts like the jets and metering rods are interchangeable between the original Carter AFB's and the currently produced Edelbrock carbs.

Carter AVS - Dodge

The Carter AVS (Air Valve Secondary) is a refinement of the basic AFB design. Whereas the AFB used a velocity valve, which is a counterweighted flap below the secondary venturi, the AVS used an air valve, which is a spring loaded flap above the venturi. The purpose of the two is similar, but the air valve is adjustable from outside the carb.

When the throttle is opened so that the secondary throttle plates begin to open, vacuum develops under the air valve, slowly pulling it open. In this way, the air flow is controlled and the mixture is kept from getting too lean if the throttle is opened suddenly.

Carter AVS carbs appeared in 1966 on the 275 HP version of the Chevrolet 327, but were never again used on Chevies after that. AVS carbs were found mostly on Mopar applications from 1968-1971. The most sought-after AVS carbs are the 800 cfm models found on 440 CID motors.

Recently, Edelbrock has been marketing the Thunder Series AVS carburetor, again reproduced by Weber USA.

Carter did not build a performance version of the AVS after OEM production in the 1971 model year.

the original carter AFB 9000 series had three basic models with
part number cast in one of the front feet (I think it was on right side).
9400=400cfm, 9500=500cfm, 9625=625cfm. if the carb part# exactly
matches the basic part# then it's setup for chevy linkage. if the last
number is 1 greater than the basic part# then it's setup for chrysler
linkage. and last number is 2 greater than the basic part# = ford. e.g.
9625=chevy 625cfm, 9626=chrysler 625cfm, and 9627=ford 625cfm.
the other twist to the part numbering is adding 10 to any of the above
examples indicates EGR provisions. e.g. #9637 ford 625cfm w/egr.

-- Edited by rabbit64cs on Monday 4th of January 2010 10:05:57 PM

Beaumont4008 · Uber Guru

rabbit64cs wrote:

I pulled down that AVS I squirelled away, wire brushed it off,, It is 4401S J7 , intended for a 68 Chrylser 383. I was clueless that chevy ran them...so now I know !!

The J7 is a date code September 67 . Would fit right in for a early 68 car.

Looks like Geof's carb is a 625 cfm (9625) date H9 August 69 or79

-- Edited by Beaumont4008 on Monday 4th of January 2010 10:18:59 PM

03cts sport · Uber Guru

Thx again for the insight guys. Other than going for originality, any thoughts as to whether or not I should try to locate an AVS?

Re the 625cfm...
I read once where it was mentioned that a guideline for carb cfm is a calculation of displacement times max rpm, then divide by 3,456. (If I use the 327 max HP rpm of 4800, the calculation recommends a cfm of 454.) Any idea of the cfm of the AVS?

(I'm thinking that this might explain why it seemingly launches in the higher RPM's. I'm thinking I may have a little too much carb?)

-- Edited by 03cts sport on Monday 4th of January 2010 10:41:55 PM

03cts sport · Uber Guru

rabbit64cs wrote:

the original carter AFB 9000 series had three basic models with
part number cast in one of the front feet (I think it was on right side).
9400=400cfm, 9500=500cfm, 9625=625cfm. if the carb part# exactly
matches the basic part# then it's setup for chevy linkage. if the last
number is 1 greater than the basic part# then it's setup for chrysler
linkage. and last number is 2 greater than the basic part# = ford. e.g.
9625=chevy 625cfm, 9626=chrysler 625cfm, and 9627=ford 625cfm.
the other twist to the part numbering is adding 10 to any of the above
examples indicates EGR provisions. e.g. #9637 ford 625cfm w/egr.

-- Edited by rabbit64cs on Monday 4th of January 2010 10:05:57 PM

Just noticed this in the light blue. So the one I have is correct for a Chevy? That's good news...
thx

rabbit64cs · Canadian Poncho Superstar!

it is for a chevy, BUT there is a pile of tuning that can be done to them. go the edelbrock site , should give you some info and guidlines for what jetting and so on.

we played with a AVS on big cam application,,,made quite a difference...

-- Edited by rabbit64cs on Monday 4th of January 2010 11:05:52 PM

Keith Tedford · Addicted!

Back in '66 two friends bought new 327 275 hp Chevelles, Oshawa built. Both had the Carter AVS (Air Valve Secondary) carbs. I put the same setup on my 283 Beaumont and it worked fine. Sure was no match for the 327s though.

4SPEED427 · A Poncho Legend!

I am not doubting you at all Keith. It is just so strange that I've seen a number of Canadian 327 cars for 66 and never seen an AVS on one. It It makes a guy wonder if the early/late listing in the parts book is totally correct. It's very obvious they made them, and likely lots of them.

It can't really have anything to do with the area of the country the car is sold in, because cars move around. If I hadn't seen it in the parts book and see you guys talk about it on here, I would have said there is no such thing.

When I was just out of high school, a friend had a 65 Parisienne 2 dr ht 327 with a Carter. That would have been a 300 horse. That's the only Carter 327 I ever saw that was factory.