What Are the Benefits of a Tunnel RAM?

by Joe White
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Tunnel RAM is a distinctive double-carburetor intake system that muscle- and sports-car enthusiasts have long favored to improve performance. The system is an intake manifold that funnels air into the combustion chamber, combining it with fuel for more explosive ignition.


The purpose of tunnel RAM is simple: to increase a car's engine performance. It is often installed in drag racers, muscle cars and sports cars, and it consistently performs as the best intake manifold system on the market.

Two Carburetors

The advantage of the tunnel RAM system is that it uses two carburetors. Most cars have a single carburetor that draws in air to blend with the fuel. Both carburetors on a tunnel RAM setup are engaged to a single plenum, which is the chamber where air and fuel are combined. The performance of a tunnel RAM manifold can be temperamental, and it depends on careful and precise installation because the system is more complicated than a single-carburetor system.

Mixing Air and Fuel

Having two carburetors allows a tunnel RAM system to provide a greater admixture of air and fuel and control the ratio of air to fuel as the two are introduced into the plenum. The cylinders of the engine, which feed directly from the plenum, perform best when the fuel and air are evenly mixed and absorbed. Mixing the oxygen in the air in with the fuel allows for quicker oxidation, more explosive ignition and greater energy transfer in the cylinders.

More Efficient

The tunnel RAM system also compensates for inefficiencies that hinder the performance of other manifolds. The dual-carburetor model is calibrated to avoid pooling of fuel within the plenum, which detracts from performance, and is more stable during acceleration and turns.


Some tunnel RAM fans choose the system especially for its distinctive look. Because the tunnel RAM is too large to fit beneath most hoods, it usually protrudes through a hole in the hood, giving the car a distinctive look.

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