Inliners International Forums General Discussion Hi Performance Flowbench experts, what's a good figure?

If the calculator doesn't ask how many cylinders, just use the actual engine size and other data, but multiply the result by 1.333.

According to Bell, the port area of a siamese intake should be 2-3% higher than the area of the intake valve as a minimum.
For a 1.94" valve (common for Gen-3 L6) that's about 3.04 square inches, equal to a rectangle 2.03" × 1.5" or a round port 1.97" ID.