Guess The Carb
09-13-11, 05:44 PM
#1
Junior Member
Thread Starter
Join Date: Mar 2001
Location: Whoseville, IL
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Guess The Carb
Attached are pics of two carbs that I have. What years are these nikkis? I think the left one is a 1981, but not 100% sure. I have no clue on the right one, but would assume an earlier year since it has less emissions junk on it. The right one also seems strange as the opening for the primaries on the airhorn seems larger.
Second question is if I am to rebuild one, which should I rebuild and put on the car... or should I somehow combine the two? I think the jets changed slightly from year to year, so which would be most optimal? Emissions is not a concern as I plan to strip either carb down a little when rebuilding.
Thanks for any suggestions in advanced.
Second question is if I am to rebuild one, which should I rebuild and put on the car... or should I somehow combine the two? I think the jets changed slightly from year to year, so which would be most optimal? Emissions is not a concern as I plan to strip either carb down a little when rebuilding.
Thanks for any suggestions in advanced.
09-13-11, 05:50 PM
#2
The one on the right looks to be an SA carb, 79 or 80, non-California build, for manual transmission. The two center-mounted mixture screws are distinctive, as is the lack of a VPV solenoid (says it's non-Cal, non-auto). Lack of a metal anti-tamper cover on the lower mix screw also says non-Cali build.
The one on the right has the double-diaphragm choke mechanism and external altitude compensator that says it's 81 or later...
The one on the right has the double-diaphragm choke mechanism and external altitude compensator that says it's 81 or later...
09-13-11, 06:46 PM
#3
meh.
iTrader: (2)
Join Date: Aug 2009
Location: fwb, fl
Posts: 459
Likes: 0
Received 0 Likes
on
0 Posts
The one on the right looks to be an SA carb, 79 or 80, non-California build, for manual transmission. The two center-mounted mixture screws are distinctive, as is the lack of a VPV solenoid (says it's non-Cal, non-auto). Lack of a metal anti-tamper cover on the lower mix screw also says non-Cali build.
The one on the right has the double-diaphragm choke mechanism and external altitude compensator that says it's 81 or later...
The one on the right has the double-diaphragm choke mechanism and external altitude compensator that says it's 81 or later...
the one on the left is 81-82. because im fairly sure the 83-85 had the different, non-triangular small AVSV. they got the little hexagonal one that screwed in. maybe someone else can verify? its either 83 or 84. guessing 83 cuz thats when the oil cooler got swapped.
09-14-11, 03:59 PM
#5
Oh, and to answer the second part of your question, the Nikki carbs changed substantially between SA (-80) and FB (81-). A surprisingly small number of parts are interchangeable.
They are very similar in operating theory, but all three portions of the body (throttle body, main body, air horn) have physical differences with regard to what passages are drilled or blocked, the design of the compensation circuits, & required solenoid valves, as well as jets and bleeds used. As I pointed out, even the number and location of the idle mixture adjustment screws changed between SA and FB years. As did most of the external cams, brackets, and diaphragms.
Jets and bleeds also change within single model years based on application (manual or auto; Fed, Cali, Canadian builds) but those are 'bolt-in' changes in comparison.
If you are in need of swap parts to rebuild/repair the FB (LEFT) carb, I may have a spare FB carb (or two) squirreled away that would be a much closer match. We could work a swap, as I could better use to have a spare SA carb. Even though it's not a Cali-specific carb, it's closer.
Let me know if interested, and I'll photograph my spares so we can compare them in detail.
They are very similar in operating theory, but all three portions of the body (throttle body, main body, air horn) have physical differences with regard to what passages are drilled or blocked, the design of the compensation circuits, & required solenoid valves, as well as jets and bleeds used. As I pointed out, even the number and location of the idle mixture adjustment screws changed between SA and FB years. As did most of the external cams, brackets, and diaphragms.
Jets and bleeds also change within single model years based on application (manual or auto; Fed, Cali, Canadian builds) but those are 'bolt-in' changes in comparison.
If you are in need of swap parts to rebuild/repair the FB (LEFT) carb, I may have a spare FB carb (or two) squirreled away that would be a much closer match. We could work a swap, as I could better use to have a spare SA carb. Even though it's not a Cali-specific carb, it's closer.
Let me know if interested, and I'll photograph my spares so we can compare them in detail.
09-15-11, 08:27 PM
#6
Junior Member
Thread Starter
Join Date: Mar 2001
Location: Whoseville, IL
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Would there be any advantage to put on the older manifold in place of the new one since the older one does not have the shutter valve getting in the way of things, or would the old manifold not be compatible with the newer carb?
09-15-11, 10:56 PM
#7
The older manifold is almost completely compatible; the altitude compensator on the old manifold (large bolt looking thing below the carb, with the u-shaped hose in your picture) isn't used with newer carbs, where the alti.comp. is on the carb itself.
More important is keeping the carb and the base isolator/gasket matched up.
More important is keeping the carb and the base isolator/gasket matched up.
