Big-Block Mopar Engines - In With The Old In With The New

We needed a bronze distributor gear to work with the steel cam core. Some hydraulic roller cam cores are made from cast iron, but this one is steel. The beehive springs are COMP PN 26120, while the roller lifters are COMP PN 8921-16.

Using studs to hold down the rocker arm shafts is highly recommended for any aluminum cylinder head. The pushrods are 3/8-inch diameter from Smith Bros. and they are the standard Mopar ball-and-cup arrangement.

These stainless steel alloy 1.60-ratio rocker arms are made by Rocker Arm Specialist. These are excellent rocker arms, but they can be difficult to find because the production volume is very low.

With the smaller port size of the Edelbrock RPM cylinder head, the pushrods can stay in the stock location. Higher performance cylinder heads such as the Edelbrock Victor heads require rocker arms with additional offset.

The timing chain set is a Hex-A-Just unit from Cloyes. Also visible is the endplay button from Hughes Engines, which is required when running a roller cam in an RB block.

The billet timing chain cover from Hughes Engines has an access cover that allows the camshaft endplay to be measured directly. The endplay on this camshaft was set at 0.009 inch.

The ignition system consists of an MSD billet distributor and a set of 8mm FireCore 50 spark plug wires. Spark plugs were Champion C61CX racing plugs.

Here's the CH-28 intake manifold with both AVS carbs installed. It weighed about 32 pounds, which was a little lighter than we expected.

We used a pair of 2-inch spacers under the carbs to add some plenum volume to the low-rise intake manifold. Big motors usually pick up power with the extra plenum volume.