Just curious about this, not that I will probably ever need to know the answer but I'm snowed in and bored .Are the 2g and 2gc carbs the same on the tri carb setup on a 66 or different than a 57/58? Probably the answer is yes but could the carbs from a 66 be put on a 57/58 tri carb manifold along with a linkage swap and eliminate the vacuum open and closed issue with the 57/58 front and rear carbs? I've never known of this being tried and just because of that it probably won't work for some reason.

Now back to my noon nap and I'll let you with smarter minds ponder this while I dream about things of a different nature.... Lost in the fifties ...Tedd

 

Hi,

Don't know the answer, but believe there were at least 2 different size bases on 2 barrel carbs, as Pontiac had different sizes on the outer ones vs the center in 64-65, 66 they made them all the same.

Considering the value of Oldsmobile tri-power carbs might be better to use Pontiac re-pops, or any 3 you have laying around.

Regards,

 

1. the 2 barrel carbs on 57-58 are smaller than 1966
2. the 2 barrel base to manifold bolt pattern is different between 57-58 and 1966
3. 1966 carbs can't be put on the J-2 manifold because the fuel inlet are on the center front and there isn't room between the back and middle carbs. 57-58 J-2 has fuel inlet on the passenger side of the float bowls and they are smaller.
4. The carburetor spacing might be different between 57-58 and 1966
5. Progressive linkage is available for the 57-58 J-2
Below is a 57-58 J-2

 

The 2G carbs do not have a choke. If I ever get my J2 installed, I will use prgressive linkage.

 

1966

 

I have everything it takes to complete this setup. Linkage kits,fuel lines,choke stat,air cleaners,long oil fill tube etc. Contact me @ pchopesq@aol.com