which throttle body will flow more?

[type85]

Single throat with 66mm bore?
Or progressive with 34mm primary and 52mm secondary?
How do you calculate surface area? pi x radius squared?

So the area of the 66mm bore is: 3,419sq mm?

34mm primar:y 907sq mm
52mm secondary: 2122sq mm
total: 3029sq mm

I assumed the combination of the two smaller bores would have more area than the single 66mm bore, but the math says otherwise!

[ChrisAudi80]

Looks like you answered your question.

[Noisy Cricket]

I'd say the single, the double looks like its angle of approach is WAY too wide. IIRC you don't ever want more than 7 degrees on an inlet or outlet or the flow gets really turbulent.