There was a point in my life where I wanted to design and build an intake manifold for my 420A. I searched all over online for formulas. I even transferred in a manifold design text book from my alma mater (VA Tech). After reading hundreds of pages of theory, it became apparent that there are two approaches. The first is use a few basic principles, common sense, and dyno several manifold designs to determine the best fit for your particular engine and needs. The second is to use sophisticated, proprietary software to design several manifolds and dyno them to determine the best fit for your particular engine and needs. A real engine is complex and unique enough that simple formulas only get you in the ballpark and software needs exceptional data to arrive at anything better. You could beat the subject to death with formulas and software only to find that your design is mediocre. In the end, you have to build several best effort manifolds and test them on your particular engine. If you want books, find Design Techniques for Engine Manifolds: Wave Action Methods for IC Engines by Winterbone and Introduction to Internal Combustion Engines by Stone. The Winterbone book is more theory than formulas regular people can apply. The Stone book only touches on manifolds for a few pages, but does have some simple formulas. See if your local library can transfer in books from a local university with an engineering department.


Corbin
'97 GSX dressed like a '95 ESi