HEAD

Head Asm, Cyl (W/Valve). To ensure reliability, purchase GM part # 25534446 Head Asm, Cyl (W/Valve). It is sometimes referred to as GM Cylinder Head. Directly from GM, genuine parts are superb with regards to quality, longevity, and fit. Every single part passed stringent quality testing, so you can be sure that it's safe, durable, and built to perform like your original parts. Vortec Bowtie cylinder heads are described as the most powerful cast-iron heads offered by Chevrolet Performance, ideal for 400-450 horsepower street and racing engines. They feature bigger valves, a thicker deck surface, and 66cc combustion chambers. They provide outstanding low-lift flow and Fast Burn performance in an affordable, cast-iron head.