It’s no secret that LS cylinder heads are a hot market right now. Everyone is looking for that last bit of power out of their design in order to proclaim themselves the baddest head on the market. However, not many of them can make the claim that they are also emissions-legal. Enter Air Flow Research and their Mongoose 260cc LS3-style cylinder head.

“We’re really targeting the Gen 5 Camaros and [LS3-powered] Corvettes with this head,” says Tim Torrecarion, Director of Marketing and Sales for AFR. “Our intake ports on this head are flowing about 384 cfm at .700 lift, which is considerably more than the stock 243 castings, and these are EPA/CARB legal making them 50-state emissions compliant.”

More than just opening up the port sizes, there is a significant amount of R&D that has gone into these cylinder heads. “One of the things we did in the Mongoose head, is take the typical 15-degree valve angle found on the LS3, and go with the LS7’s 12-degree valve angle,” Torrecarion explains. “Then we put in a .750-inch deck thickness into the design and increased all the wall thicknesses. If you’re running a lot of boost, or spraying a lot of nitrous, this head is going to have a lot more durability than the OEM piece.”

Those features, coupled with availability in both four- and six-bolt patterns, make the Mongoose 260cc LS3 cylinder head a multi-faceted performer. Whether you have a street car in a part of the country with heavily-regulated emissions compliance, or a performance build that will stray away from the naturally aspirated path, the Mongoose heads fit the bill. “With our CNC porting, we can take the same runner volume and get more air pushed through than the competition,” Torrecarion concludes. “We’re comfortable saying, that runner size to runner size, we’re going to outflow the rest.”