Ford Carb size per Classification Guide
 

1978 Ford. Trying to clarify here. Looking at the Nhra blueprint guide. For the carb size it's listed as:

Carb Sizes - 1260 x 1420/1023 x 1064

My question, what number do you use? Is this two seperate numbers for different carbs? Do both these sets of numbers come into play somehow? Forgive my ignorance, just trying to interpret the information.

Re: Ford Carb size per Classification Guide
 

My understanding is it refers to the primary and secondary venturi and throttle bore measurements.

Jim Mantle U/V/SA 6632

Re: Ford Carb size per Classification Guide
 

That looks as if it's under the 2.3, the Holley/Weber carb. the 302 shows a Ford carb. You may have to refer to your tech director, but the 302 should be the 1.08 venturi Autolite? That's what came off my 78-vintage motor. I have a 79-vintage D9DE which is also, a 1.08 venturi Autolite.