Carb id

[cliffordl]

Hello all,
   
   Can anyone help with my trying to identify which Holley carb. I have fitted, all I can see is an alloy tag stamped AUTOLITE C8 AF B  / C7H30, the main body is stamped 4 C.B and 8P on the other side. I'm trying to source the correct re-build/service kit and my parts guy thinks I should have an LST number?

[cliffordl]

Further investigation points to this being a Carter AFB carb (now made by Edelbrock) ...still I can't find a specific model number. All advice still welcome.

[Emmanueld]

If it says Autolite is is not a Holley of a carter, it is an Autolite carburetor (Ford) installed on 428 motors in the late 60's to replace the holley for emission reasons. I will try to locate a photo! Carter AFB never fitted to the 428 engine. Holley or Autolite only.
   
   Emmanuel

[Emmanueld]

C8 AF-B refers to an Autolite 4300 4V with Cruis-O-Matic. According to my Ford book, The carburetor came on 1968 Ford cars with 390 engines and automatic C6 tranmissions, so it's probably not your car's original carb, (hopefully the engine is original and not a 390 which looks exactly the same externally). Beginning in 1967, Ford started seeking improved emissions with the Autolite 4300 4 barrels carburetor. the 4300 was not half the previous Autolite 4100 in term of performance and reliability. It was rated at 441cfm which was way too small for a big block. My advice is toss the thing and upgrade to a Holley 735 from the 428 Cobrajet!
   The 4300 carburetor is hard to tune properly and no parts are available from Ford. (You are right, the Autolite 4300 looks a lot like a Carter AFB however, it is a completely different carb)
   
   If you want to stick with it, there is a company which repairs them. However, I have no experience with them! Myself, it would have been in the trash can long time ago.
   
   http://www.ponycarburetors.com/default.asp?page=carburetors
   
   This site's comments on the Holley 4150 suggest to me that they might not be a serious company. Watch out.
   
   Regards,
   
   Emmanuel

[cliffordl]

Thanks Emanuel
   
   Doc Carburetor in the States identified it for me as a 4300 and are sending me a rebuild kit (which I'll install for the time being) - meanwhile how do I check out that I have the right 428 block?

[Emmanueld]

Clifford, Here comes the tough part! AC did not use the 428 Cobra Jet or Super Cobra jet Engine, They used the plain 428 motor probably for cost reasons (I understand a few cars were built using 427 motors upon special customer orders). The basic 428 block used the same casting as the 390. Bore was increased from 4.05" to 4.13" and stroke went from 3.78" (same as the 427) for the 390 to 3.98" for the 428.
   Most 428 blocks had 428 stamped inside the center freeze plug. No other FEs' were stamped that way. However, I would not remove any freeze plugs unless you have to. So I would look at the  harmonic balancer for identification instead. All FE engines are internally balanced except for the 410 and 428 which require counterweights on the flexplate (Flywheel for Automatic Trans) and on the harmonic balancer. If you pull the harmonic balancer and the spacer has a counterweight, your engine is a 428, if the spacer is just a sleeve, you have a 390. I think it is the only reliable way to find out for sure. It's a 20mn job for a mechanic with the proper puller. Ford did not use engine numbers until the early 80's and it's a problem to identify FEs' because they are so similar. A 427 side oiler is easy to identify because of the cross bolts on each sides of the block and the extra oil galery, also most other parts were proprietary as well. A Cobrajet motor is relatively easy as well since it uses different heads and intake manifold than other FEs'.
   
   Good luck! []
   
   Emmanuel

[cliffordl]

On receiving my carb rebuild kit and inspecting the insides I decided to send it for professional rebuild with doc carburetor in Canada.
   He notes;
   "One question - how would you like the choke setup?  It's been converted to manual choke.  I can restore the original type hot air choke, which requires a hot air tube from the manifold, or I can build it with a Ford OEM-type electric choke."
   
   I know we suspect that this is not the original carb. but until I find a (so far hard to source) Holley 735 I intend to continue with it.
   What does the 'panel' recommend re; the choke?
   
   All thoughts would be most welcome

[nikbj68]

1 vote for manual.
   Nik.

[Emmanueld]

Electric choke! easy to set-up no cable, no hole anywhere.
   
   Also easy but pricey: 1968 Cobrajet Holley 735 carb as 1968 GT500 Auto box: C8OF-9510-AB New old stock or remanufactured! Also there are some other date codes the are cheaper! all 735 cfm + they don't need to be rebuilt and jetting should be close. The choke is electrical so they are easy to setup, one wire to ground and one to a positive source like the coil, that's it.
   
   http://www.carlsfordparts.com/main.html?carbs.html~content
   
   Carl's ford parts, Good company if a bit pricey, but then not in Euros!
   
   Emmanuel []

[aex125]

If I lived in a climate where I needed a choke I would go with a manual version if the car was set up to easily accept one. If it was not an easy installation, I would go with an electric version.
   Jay