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| | | | Joined: Feb 2012 Posts: 112 'Bolter | | 'Bolter Joined: Feb 2012 Posts: 112 | Would any of you know where to find the detailed specs for zenith carbs? I found a site once that had all the specs for the different carbs but can no longer locate it.... looking to find details about jet sizes, venture sizes, base size, throat size, etc...
looking to compare zenith carb 2341685 11963 with 2343632 11965. I will be putting this on a 1962 chevy 261
thanks..
Old Truck addict
1950 chevy 1 ton napco
1956 gmc 1 ton dually napco
1954 chevy 3/4 ton napco
1957 gmc civil defense napco panel
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | | | | | | Joined: Feb 2012 Posts: 112 'Bolter | | 'Bolter Joined: Feb 2012 Posts: 112 | ive seen those breakdown pics but am looking for numerical specifications if they exist...
Old Truck addict
1950 chevy 1 ton napco
1956 gmc 1 ton dually napco
1954 chevy 3/4 ton napco
1957 gmc civil defense napco panel
| | | | | Joined: May 2002 Posts: 44 'Bolter | | 'Bolter Joined: May 2002 Posts: 44 | I have not seen a site that breaks down all the Zenith carbs like that but I did look up the two numbers in my Zenith data book.
11963 specs are as follows: Model:228BV11, Venturi #33, main jet #31, Power jet #20, well vent #16
11965 specs are as follows: Model:228BV12, Venturi #34, main jet #33, Power jet #18, well vent #15
Both were used on late 50's GMC 270 engines. Jetting and venturi sizing may be too big for your 261. Check mount hole spacing as these were different among the GMC Zenith carbs based on application.
"The Operation of GMC trucks is normally smooth and steady, with no loud rattling, knocking or unusual noises. A good driver will quickly become accustomed to driving a GMC truck and will get the feel of his vehicle regardless of his engineering knowledge."-TM10-1563
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