We found Dart Machinery’s new PRO1 LS7-compatible heads in the main hall of the Las Vegas Convention Center, a fitting environment to get a closer look at the company’s latest release. According to Dart’s National Sales Manager, Mike Sanders, the new cylinder head is offered in two variations. “The first is with Dart’s standard-rocker bar with standard bolt-hole locations and billet rail to help maintain valvetrain stability,” he said. “The second variant is upgraded with 7/16-inch bolt holes for a Jesel rocker bar. These are moved .030-inch closer to the valvetrain for better geometry and stability.”

These aluminum heads have some obvious differences when compared to the OE LS7 heads. The CNC’d rectangular-port cylinder heads have been opened up from the factory size of 259cc to 285cc for better flow on the intake side. The intake valves are still 2.20 inches, but the exhaust valves have been enlarged slightly, from 1.61- to 1.625-inch.

In addition to the valvetrain variations, another big difference between the stock design and Dart’s, is in the combustion chamber. The combustion chamber has been reduced from the factory head’s 70cc chamber down to 66cc on the PRO1. 

Outside of these performance changes, the Dart heads retain stock valve angles, stock valve location, and stock valvetrain-mounting dowel holes. All of these features will make the install of the heads easy and trouble free.

For more information on Dart’s new PRO1 LS7 cylinder heads, or its other fine products, visit them online at dartheads.com.