What is the difference between plane and tunnel ram intake manifolds?

I am assuming that you mean the difference between a dual plane and single plane intake manifold on a gasoline engine and that the engine uses a carburetor to mix the air and fuel. Generally speaking, what you are referring to as a tunnel ram manifold is designed with a large open area, or plenum, under the carburetor intake flange and has no tunnels at all. this design is for high rpm racing only. That kind of racing requires maximum air flow and will have very poor throttle response on a street car. The dual plane manifold has cast in runners that separate the incoming air flow from the carburetor flange to each intake port in the cylinder head. This design will give good throttle response and performance.

Aftermarket intake manifolds are all designed for a specific rpm range and the manufacturer will have any information you may need on their website or help telephone line.