ABOVE: Dean Beliveau, of Ontario, shown (left) working on a 427 carb with two buddies. Good help like this is hard to find!
Many Chris Craft engines were provided with the
Carter AFB carb. It was introduced in 1957 and the following year Chris Craft introduced the Chevrolet based 283 V8 in their inboard speedboats. The AFB was offered on many of the small block Chevrolet motors, and also on the Ford 427 marine engine, and probably on the 431 Lincoln as well.
The Carter AFB (Aluminum Four Barrel) comes in many sizes, and it has been used on all kinds of muscle cars over the years, especially during the horsepower wars of the 1960s on the GTO, Chevy 409, and Chrysler Hemi, many small block Chevys, Avantis, just to drop a few names..
Here are some documentary shots. The first series of photos are from a 427 marine application, and this particular set of carbs was eventually replaced by the owner at the time the engines were installed.
The second series of photos is from my 1956 Chris Craft 17-foot mahogany speedboat, during the time I was installing a 327 that came out of a Chris Craft Super Sport. This particular project proved to be a classic engine swap, going from 120 to 300, give or take a few.
These photos document what a Carter AFB looks like in a marine application. They may be helpful references when discussing how to tune a motor, etc, which jet to turn, etc., and that is the reason they are posted on the site. Happy reading!
Paul
Looking down the top (front of the motor is toward the bottom of the photo).
View from the port side, you’ll note Ford installed the distributor in the proper location at the front of the motor.
Rear view of the Carter AFB as installed on a marine 427
Starboard view of the AFB. They obviously were run hard and long.
Here’s a photo of my speedboat setup, photo taken several years ago. I’m not real sure what size this carb is, but I rebuilt it, I never really determined all of the jet settings, size, etc. The boat runs very strong.
Another view. Sorry for the dust, this was during an era when finish sanding was under way, and the motor was just lifted into the boat for final fitment to the stringers.
Top view of the AFB in small block service. That’s an Edelbrock Performer intake by the way, and if you look closely you can see the stringers were just drilled for the big lag bolts through the motor mounts. This was done after custom reinforcing of the stringers with epoxy and white oak, with stainless steel through bolting. Since there are eight fasteners holding this motor down, I stayed with the lag bolts rather than going with stainless steel threaded rod and locked nuts. If it was a Jersey Skiff, I’d want the motor held down more securely.
Here are the specs on the original Chris Craft Carter AFB
Original Equipment Chris Craft Carter AFB specifications (427 Ford)
Carb ID number is 4157 S
This is a 625 CFM unit.
Primary jet is .1015
Secondary jet is .086
Metering Rods are two step, first step (power) is .055, and the
second (cruise rod) is .061
You can almost buy the exact same carb
from Carter, with improvements of course (hey, they have learned a
thing or two about carbs in the last 35 years, no longer use leather,
for instance). Edelbrock has a 600 CFM unit that matches up pretty close, but
Carter has a 625 marine which is even closer, but the jets on both of
these are a tad different than the ones selected for the 427 Ford..
By comparison, the (generic) marine Edelbrock 600
Primary jet: .098
Secondary: .101
Metering rods: .068 x .047
You can buy any rod or jet you want for a few bucks, the parts
interchange between the Carter and the Edelbrock (so they say). You can even buy the electric choke kit.
Here is a location that sells all the individual parts, it is not the best location to buy a new AFB (prices are high)
http://www.carbs.net/Carter4.htm
Great info on how to size and tune a carb (you can see here, there is no need for more than 600-cfm on a marine 427 motor.) Since the charts indicate a 427 marine engine that spins only 4000 rpm max won’t even need 600 cfm, the 600 cfm marine Edelbrock is probably a good choice if you’re interested in a new replacement
http://www.federal-mogul.com/fmeconnect/technicalservices/downloads/1601.pdf
Here is a writeup I found that pretty well lists the basic concepts of a Carter AFB.
Aluminum Four-Barrel (AFB) carb was there, and it's never gone away. The AFB design still enjoys a loyal following, and for good reason. It's a simple carb to tune and rebuild, and it makes great power. Today, the basic design of the AFB has been adopted by Edelbrock as the basis of its Performer series of carburetors.
Performers, like all AFBs, use metering rods attached to spring-loaded step-up pistons to provide fuel enrichment as the engine transitions from light-load, low-fuel-demand situations like cruising and light acceleration to high-load, high-fuel-demand situations like wide-open throttle acceleration. Metering rods can be swapped in minutes without disassembling the carb and allow you to richen or lean the mixture by up to about 8 percent in either direction without changing jets.
Here is a complete rebuild and tuning guide for the Carter clone now being built by Weber/Edelbrock
http://www.carcraft.com/techarticles/1071
Happy reading, happy cruising!
Paul
