Edelbrock Victor 440 Cylinder-Head Test

By going to a smaller rod journal (2.375 to 2.200), you have to remove quite a bit of material from the crank. Taking it all from the near side of the journal moves the rod center line away from the main center line, which increases the effective stroke. In our case, it works out to be about a 0.165-inch increase adding about 21 ci to the displacement. So for all you guys wondering how we came up with a 466-inch motor, that's how.

ARP fasteners were used throughout the build. The bolt-torquing sequence was performed three times to even out the friction in the threads. The torque force applied is really just to overcome the friction and to ensure the correct amount of fastener stretch. ARP suggests you go through the torque sequence a minimum of three to five times to ensure even bolt stretch. If you're going to spend the extra money for top-quality hardware, make sure to follow the instructions on how to install it.

Great attention to detail was paid to the combustion chambers of the ported Performer RPM heads during the first test. By tracing the shape of the head gasket onto the head, we were able to see exactly how much material we could remove to help unshroud the valves. All the sharp edges associated with the insertion of the valve seats were massaged, and any irregular contours in the chamber were smoothed to promote better flow. After all the material removal, the whole chamber was worked with a Scotch Brite pad. The dyno numbers told us all the extra work paid off.

The increased overall height of the Victor 440 head (left) is obvious in this photo. The extra material cast into the intake side of the Victor allows you to use a standard 440 (RB) manifold without spacers. That means when you do a swap from a stock set of heads or Performer RPM heads like we did, you can still use the same manifold. The holes on the right head are left over from a material-thickness experiment. Don't worry, it was half a sample head we got from Edelbrock.

Exhaust-port flow has always been an issue for the big-block Chrysler. Edelbrock engineers not only increased the overall size of the port to 100 cc in the Victor head (left), but they also raised the port 0.250 inch to improve flow characteristics. The intrusion of the valveguide into the port has also been minimized.

To improve the angle and flow of the intake ports in the new Victor head (right), Edelbrock engineers raised the port openings 0.650 inch. It worked. The new port position yields an impressive intake flow number of 325 cfm at 0.700-inch lift.

The closed chamber of the Performer RPM and Victor heads provides dual quench areas that you can clearly see outlined on the piston. These pistons have 23 dyno pulls on them and still have clean areas clearly visible. Notice the clean, angled areas that mimic the spark-plug positions in the head. Make sure to put your pistons at zero deck height or higher to take full advantage of the antidetonation characteristics of the close quench design.

The exhaust-port modification on the right is the only major change made to the ported Performer RPM head. Basically, we copied the design of some modern, high-performance heads by creating a D-shaped port. The overall width stayed the same; only the roof of the port was changed. The intake side was just squared up and cleaned with a sanding roll, no other changes were made. The rest of the work was performed on the bowls, combustion chamber, and valve job. Edelbrock castings are very clean, so there really wasn't much to do. Anybody can get these results at home without a big investment in expensive tools.