Previous discussions (on another forum) have indicated the long runner length of the stock manifold as a one of the obstacles to high RPM flow. Basically my idea for the intake manifold is a Dbilas style setup, minus the individual throttle bodies of course.
My two main concerns are: 1. Size of the airbox 2. Shape of the airbox
I want to make sure the airbox is large enough and will replenish fast enough for each intake stroke of the crank. I don't know how many of you are familiar with sportbike stuff and so called "Big Bang" bikes, but for instance the new R1 uses a wildly timed crankshaft to improve smooth running etc, lots of discussion about piston speeds and throttle response and E36 M3, but the main reason they don't just have a piston firing every 90° of crank rotation is that the airbox would not be able to refill fast enough for each intake stroke.
A simple rectangle with the throttle body on the side, ie exactly like the Dbilas setup or a "house" shape with the side of the rectangle slanting outwards to long side, or even more a 666fabrication style intake (which also matches the E46 M CF airbox I think).
The plan is to start researching and gathering parts so I can build a 3.1L high compression N/A M20 for the E30.
Which I know what parts are needed, the last variable to research is the intake manifold.