Inside A Ram Air V - Pontiac Tech

The Delco-Remy capacitor-discharge amplifier was also found and used in the buildup. These C-D ignition systems were production units and were optional on GTOs in 1967.

Machined 72cc combustion chambers were unique to the 400 and 428 versions of the Ram Air V. The shape of the chamber was also unique to these engines. The 303 used a 56cc, rough-cast chamber that was very different in shape. Note that unlike other Pontiac heads of the era, the spark plug of the Ram Air V is more centrally located and angles toward the exhaust valve, the hottest part of the chamber, to promote more efficient combustion.

Individual exhaust ports are the easiest way to distinguish a Ram Air V engine from all other Pontiac V-8s. The revised placement necessitated a unique camshaft. The valve placement was EIEIIEIE, as opposed to the regular production placement of EIIEEIIE.

Huge intake ports placed the pushrods right in the middle of the port. Airfoils were used on most versions to aid airflow around the pushrod tubes. The intake ports flowed significantly more air than 426 Hemis or rectangle-port big-block Chevys. This design was largely derived from the 427 Tunnel-Port Ford.

The large oval ports were designed for maximum high-speed performance and weren't conducive to normal street operation. Note these heads didn't feature any provisions for manifold heat, further hampering street performance.

Other than their unique placement, the R/A-V exhaust ports were actually quite similar in design to the production Ram Air IV. The mismatch in size relative to the intake (324-/209-cfm intake/exhaust flow) resulted in somewhat hampered performance, especially with the stock camshaft specs of 308/320-degree duration with 0.520/0.520 lift.

These three shots show the dramatic differences between the Ram Air V heads, the round-port Ram Air IV heads, and the production D-port Ram Air IIIs.

The most striking differences are, of course, the shape and placement of the exhaust ports and those huge Ram Air V intake ports.

The R/A-III and IV heads feature 2.11/1.77 valves and the R/A-V head has 2.19/1.73 valves. (This Ram Air V head, however, has 1.74-inch exhaust valves due to valve-seat wear.)

As the Ram Air V engine-block design is different from other production Pontiac V-8s, it isn't possible to fake one. However, the experimental and low-volume nature of the Ram Air V engine program is evident in the hastily hot-wiped raised casting and restamped block number-this stamp was actually done by the factory.

The casting date of this block is January, 21, 1970 (A210), during the night shift, making this one of the so-called '70½ Ram Air Vs.

How close did the R/A-V come to production? Specific block codes were assigned. The WY code was intended for a production GTO application.