With the offering of the new PBM-Erson-World Products CNC-ported iron heads, racers and rodders alike can now get a budget-friendly head with CNC porting.
“What we’ve done is taken our four most common iron heads, two big-block and two small-block designs, and increased the out-of-box performance by about 25 to 30 percent over what you would normally see,” explains PBM’s Brad Sauls. “The Sportsman line of small-block heads are ported to 215 cc, and the Motown SBC head receives CNC porting to a 230 cc intake runner.”
“Circle track and pulling applications jumped upon these heads,” noted Sauls. “They’re not just limited to those motorsports…off-shore marine is also a good place for these heads because saltwater can play havoc on aluminum. Today though, lots of index class and budget bracket racers are building new larger cubic-inch and high-RPM combination with these heads.”
As an example of flow improvement with the big-block Merlin heads, both heads support 2.300/1.880-inch valves. The 365 cc intake runner heads flow into a 128 cc chamber, while the smaller 340 cc intake runner is paired with a 123 cc combustion chamber.
The airflow numbers for the intake side posted by World Products show 403 cfm at .800-inch lift on the Merlin 340 and 428 cfm at .900-inch lift on the Merlin 365.
“The engine builders attending the PRI show are taking a keen interest in the World Product lines because we offer these heads unassembled. That means shops can customize and build these heads for their specific customer needs,” adds Sauls. “With our business-to-business effort, we have already seen reported success with these heads producing more power and already winning races.”