Challenger Intake Manifolds: Increasing Lung Capacity

The intake manifold is made up of two parts: the runners and the plenum. On some vehicles, the plenum is a replaceable and upgradable component.

On the Challenger, this plenum is a part of the intake manifold itself. The plenum is the area in the intake manifold where the air is first drawn in to. As vacuum is developed by the cylinders, they suck the air through the runners and out of the plenum.

Considering an aftermarket intake manifold comes into play when your typical bolt-ons won’t cut it. An intake manifold is an expensive modification but will increase horsepower by allowing more air to be drawn into the cylinders.

If bottom end modifications are made to make more power or enough bolt-on upgrades have been added to raise power, an aftermarket intake manifold will help the engine take full advantage of your other mods.

Runner Length: The runners play a crucial role in delivering air to the Hemi combustion chambers on your Challenger. Aftermarket intake manifolds may change the length of the runners. This is done to help ensure that all the available air is drawn into the cylinder before the valve closes. Varying lengths will serve different engines.

If the engine is relatively stock, it’s not likely that much need be changed in order to get all of that air in. If the engine is modified these lengths can be changed to help provide optimal performance.

It’s important to remember that an aftermarket intake manifold isn’t going to add power; it simply works to allow more power to be made.

Materials: Aftermarket intake manifolds for Challengers may come in aluminum construction. This will help dissipate heat.

Hot air is less compressed than cool air and will contain less oxygen. With the use of materials that dissipate the heat more oxygen will be present and more power can be made.

Porting: The length of the runners is just as important as the width. Some aftermarket suppliers will sell what is otherwise a stock intake manifold with ported runners. Porting the runners opens the width, which allows for more air to flow through. It’s good to know that machine shops and engine builders will be able to port intake manifolds for you. This means you can have your stock manifold worked up or if you find an aftermarket manifold you can take it to be ported as well to further boost performance capabilities. 

Basic mods will benefit from the use of an intake manifold. More airflow is always better. However, when you start looking at aftermarket manifolds for a Challenger you may be wondering what warrants totally changing this component rather than modifying it.

Complimentary Modifications: An intake manifold is meant to be taken advantage of, and you will want an engine that will take advantage of it. The bottom of the engine is what produces vacuum.

Bigger bores and longer strokes will produce more vacuum and draw in more air. Aggressive camshafts will hold the valves open longer which will allow the engine to pull in more air.

Ported and polished heads or aftermarket heads will allow much more air to pass through. All of these mods will be best paired with an aftermarket or modified intake manifold that can provide the engine what it needs.

All naturally aspirated engines leave the intake with one major weakness; they are waiting on the cylinders to produce a vacuum in order to draw in air. This is how they allow more horsepower to be made but don’t necessarily produce power. There is an option that changes all of that though, and that’s a supercharger.

Roots/Twin Screw Style Superchargers: Roots superchargers are the types of superchargers that can be found on Hellcats and Demons. Both roots and twin screw units feature two turbines in the housing of the supercharger that’s spun by the accessory belt.

As these gears spin, they produce a vacuum that pulls in air and then forces it into the engine with positive displacement. These units completely replace the stock intake manifold rather than feeding into it.

Centrifugal Superchargers/Turbos: Roots and twin screw superchargers feed boost directly into the cylinders. Centrifugal superchargers and turbochargers both rely on fans. How the fans are spun is what separates them but where they send the air is the same.

These units produce boost by pushing air through the throttle body and into the intake manifold. The intake manifold will not be replaced when these are installed.