The Ram Induction System
revised 10/27/03

Chrysler 300 Letter Cars have always been about power and performance. From 1955 to 1958, power and performance meant dual carbureted Hemi engines. In 1959, it meant dual carbureted wedge engines. In 1960, power and performance meant Ram Induction.

If you can increase the mass of air flowing through the engine, you can increase power. You can increase air flow either by an external device such as a supercharger, or you can increase air flow by designing resonance into the manifold systems. The Chrysler "Ram Induction" manifold is a resonating manifold.

Although the Chrysler advertising men said ram induction was new for 1960, the idea goes back 97 years earlier when Hermann Ludwig Ferdinand von Helmholtz developed mathematical equations for acoustics and resonance. When Chrysler chose to match the intake system to a 2800 RPM engine speed, the Helmholtz equations said 30" long intake tubes would be required. Through some creative thinking, Chrysler was able to package eight 30" long tubes under the hood. This was the result:

The ram induction system in its naked glory,
without carbs and paint and linkages.

More Than You Ever Wanted To Know About Rams

There are Long Rams.
There are Short Rams.
There are water heated Short Rams.
There are exhaust heated Short Rams.
But all Long Rams are exhaust heated.
Confused yet?

Long Rams
Long Rams were standard equipment on 300Fs and 300Gs.
They were designed for peak torque at 2800 RPM.
They can be identified by the valley between the runners as shown.

Long rams also have a 7 digit casting number that begins with "19".

Short Rams
Short Rams were standard on the 300J and were used
on the optional engines for the 300F, 300G, 300H, and 300K.
Short Rams were designed for peak torque at 3600RPM
This is a short ram induction system in a 300J.

Short rams can be identified by the lack of a valley
in sections of the intake runners just downstream from the carbs.

Short rams have a 7 digit casting number that begins with "21".

Ram Trivia
All long rams were exhaust heated.
Not all short rams were exhaust heated:
300J and 300K short rams were exhaust heated but
all other years of short rams were heated by water.
Here is a picture of an H with water heated short rams.

There were some differences in long rams:
Some rams had pins to serve as throttle return spring anchors.

Some rams had brackets from the carb base for throttle return spring anchors.

The cam gear is special for the ram cars. The gear has the cam locating pin hole retarded 2 degrees that makes the crank gear timing at the damper 4 degrees retarded but does not effect the specific timing of the engine according to the factory ignition timing sequence at the damper. This "retarding" affects the mid to high range torque output of the engine. The combination of the cam retard and the ram action produces optimum horsepower and torque. Engines rebuilt with the "standard" cam gear produce 10-15% less power and torque.

The photo below shows some of the spark plug wire holders used on ram cars.

If you haven't had your fill of rams yet
click here to go to 'Ram Theory'