Dart Race Series 15° Non CNC Ported Small Block Chevy Cylinder Head PN 14300000C. This head is a bare non cnc ported casting. The Dart Race Series 15 degree head can be ported to 284cc's. They deliver awesome performance and the shallow valve angle, reshaped raised intake ports and optimized combustion chambers produce a significant increase in both airflow and combustion efficiency. Everything will be done with the exception of the porting and valve job. This is my very LAST 15 deg Cylinder head. The item "Dart Race Series 15° Non CNC Ported Small Block Chevy Cylinder Head PN 14300000C" is in sale since Friday, February 9, 2018. This item…