[Richard/SIA]

Tried to look this up on the 'Web with no success.
I need to know the bore and spread of Rochester 2GC carb bases.
The stud pattern would also be helpful.
Hoping these use four bolts not three?
Looking at converting an old manifold to upgrade with Weber DCNF 42's if feasible.
Weber specs are easy, I have them in a book.
Rochester 2GC are much harder to find than expected.
TIA.

 

[GLHS60]

Small 4 bolt pattern carbs were used on 210 HP 327 Engines and lower.

Large 4 bolt pattern carbs were used on 235 HP 327 Engines and higher.

Thanks
Randy


From: http://www.chevyclassicsclub.com/wp-content/themes/chevyclassicsclub/pdf/tech0213.pdf

The Rochester 2G carburetor was introduced in 1955 and was used in various applications by all GM divisions through 1979. It is easily identifiable by the words “2 Jet” on the air horn (lid). This carburetor was made in two base sizes. The original “early” size has center to center stud dimensions of 2” x 3-¼” and a bore size of 1-7/16”. The larger base stud dimensions are 2” x 3-¾” with a bore size of 1-11/16”. In all, 5 cfm (cubic feet per minute) sizes were produced, ranging from 278 cfm to 435 cfm (see chart on page 11 for details). The difference in cfm allowed the versatility of this unit to be factory installed on smaller engines such as the Chevrolet 265 and 283 cubic-inchers. The largest 2Gs were used on the Chevy 400 and Pontiac, Olds, and Buick 455 engines in the early ’70s. By designation, there were three versions of the “2 Jet”: • 2G has a manual choke • 2GC has an integral choke assembly with black choke cap • 2GV has a remote mounted choke assembly (on the intake manifold) with a vacuum pull-of

 

[Richard/SIA]

Now if I could only find the distance between centers of each barrel.
It looks like a conversion should be possible.
I do not have any 2G's available to measure.
Two 40 or 42 DCNF's will flow over 600 CFM so plenty for a little 215 Buick/Rover.
Advantage of the DCNF is greater flow and tune-ability over 2G's.
They also look a lot better than the 2G's.

 

[makemfaster]

Buy a base gasket from an auto parts store.

 

[B52bombardier1]

I've got the old 2G something carb from my derelict 70 El Camino 350 engine here that I can measure the distance between barrel centers.

Rick

 

[Richard/SIA]

Not so easy as you would expect.
Anything over ten years old seems to be special order now.
Just went through heck trying to fix brakes on a 2002 "F" truck.
Seems Summit is becoming the only easy source for vintage, and even they are less useful now than before.

 

[MidLife72]

Try Rock Auto