Originally Posted by NCoonis
Dave, I could be wrong but I thought the formula for area of a circle was radius squared x pie. So in my case I'd have:
.75/2= .375 radius
.375 x .375 = .1406 radius squared
.1406 x 3.14 = .4415 square inches of one 3/4" circle
.4414 x 4 = 1.766 is my total intake.
A 3" exhaust using the above formula would give me a 7.06 sq in exhaust.
I'm going to look for a airflow calculator now to see where I should be at.
You are right, missed the squared step.