Definition of Tunnel RAM
- A Tunnel Ram intake manifold is one which uses two carburetors instead of one, harnessed to a single plenum, for the purpose of optimizing the fuel-air ratio for combustion.
- The Tunnel Ram system is an alternative to the more common single-carburetor setup. It requires more careful adjustment because it is an unconventional arrangement. More recently, single-plane intake manifolds have improved greatly. They are almost as good as the Tunnel Ram inlet, and much easier to install and adjust.
The intent of the Tunnel Ram was to use two carburetors to mix greater amounts of fuel and air for introduction into the engine, while limiting inefficiencies such as pooling of the fuel on the sides of the plenum and spillage, especially on turns. - The Tunnel Ram system was invented by a team of street racers in the 1950's, who first demonstrated its use on a 1949 Plymouth. Since its inception, it has enjoyed continual popularity, in no small part due to its distinctive look, which cries out "muscle car!" or "racer!"
- As single-plane manifold technology has improved (while Tunnel Ram systems are becoming no easier to manage), some performance-minded drivers have argued that the new technology has superseded the Tunnel Ram. Comparative testing has shown, however, that the Tunnel Ram is still the most powerful manifold system, provided that it is installed and managed correctly. While advocates of the easiest and most reliable intake manifold prefer single-plane systems, the most traditional and most determined performance teams continue to prefer the Tunnel Ram system.
- A Tunnel Ram system is more expensive than single-plane systems, typically ranging from $800 to $1500. It requires additional coupling units to fit it to most engines. Nonetheless, it enjoys popular support as the top-of-the-line intake manifold system.