FA Engine Code in 1969 indicated:
327 cid engine; manual transmission application
235 Hp 2Bbl - SAE size 1-1/2 Carb
From a Full Size Chevy
The "3927185" heads are the base heads for the 235 or 210 Hp 327 engine in '69. They have .174" dia intake and .154" diameter exhaust valves. The intake valves can be enlarged to .194" diameter.
The difference between the 235 and 210 Hp variants of the 327 in '69 basically boils down to the intake and the carbs. Both versions use a Rochester 2G carb (2GC or 2GV). The GV variant has a divorced choke coil mounted on the intake manifold, the GC variant has the choke coil mounted on the carb body.
For the 235 Hp version of the 327 (Full size passenger cars), the Rochester 2Bbl carb is a size SAE 1-1/2; while for the 210 Hp version (Camaro, Nova) the Rochester 2Bbl carb size is SAE 1-1/4. The SAE 1-1/2 carb has larger throttle plates and a larger air horn than the smaller SAE 1-1/4 variant. Consequently, both the intake manifold as well as the air cleaner are different for SAE 1-1/2 vs. SAE 1-1/4 carbs.
The following is quoted from the Delco Carburetor Models 2G, 2GC, 2GV Service Manual; 9D-3; MAY, 1973 and at the following link: http://www.tocmp.com/manuals/Carbs/Rochester/2-Jet/Manual/MCarbRoch1973__2G_0003.htm
There are three basic model "G" Rochester two-bore carburetors. They are the Models 2G, 2GC and 2GV. The basic model designation is "G." The (2) ahead of the "G" means the carburetor has 2 bores, 2 venturii and 2 separate but identical metering systems, one for each carburetor bore. The 2-bore carburetor is normally used on V-8 engines where each bore supplies air and fuel to 4 cylinders through a divided intake manifold. There are two different throttle body flanges used on the Rochester 2-bore carburetors. They are SAE (1-1/4") and (1-1/2"). The flange size used for a particular application is usually determined by the carburetor bore size. Larger engines normally have more air capacity, hence, larger carburetor bores and flanges are needed on these applications.
The Model 2G carburetor is equipped with a manually-operated choke valve. Its major applications are on truck and marine engines where an automatic choke is not an absolute necessity.
Some 2GC, 2GV models use a vapor cavity or vapor dome in the cluster to improve fuel vapor handling in the main well. The cavity or dome is a recess at the top of the cluster to allow any vapors collected in the main well during hot operation to be condensed instead of being pushed into the carburetor venturi to disrupt engine idle or hot engine starting.
The Model 2GC carburetor is the basic model 2G unit except the "C" designates an automatic choke which is an integral part of the carburetor unit. The automatic choke housing with thermostatic coil may be located on the air horn or throttle body, depending upon the application.
The Model 2GV carburetor is also an automatic choke model; however, a vacuum break diaphragm unit(s) is used in place of the conventional choke housing and choke piston. The choke thermostatic coil is located on the engine intake manifold and is connected to the choke valve by linkage.
The Rochester Models 2G, 2GC, 2GV use the calibrated venturi cluster design that places in a removable assembly the main well tubes and pump jets. The cluster mounts on a flat portion of the carburetor bowl, at the side of the main venturi. A gasket is located between the cluster and the mounting pad. The idle and main well tubes are permanently installed in the cluster body by means of a precision press fit. The main well tubes and idle tubes are suspended in the fuel in the main wells of the float bowl for insulation from engine heat, thus helping prevent heat expansion and percolation spill-over during hot idle and short periods of hot engine stops.
Some 2GC, 2GV models use a vapor cavity or vapor dome in the cluster to improve fuel vapor handling in the main well. The cavity or dome is a recess at the top of the cluster to allow any vapors collected in the main well during hot operation to be condensed instead of being pushed into the carburetor venturi to disrupt engine idle or hot engine starting.
