Like the L98 Corvette head, the LT4 casting ushered in the next generation of high-performance GM performance small-blocks. The LT4 head has the latest in GM Performance Parts technologies with all of their high-end quality materials. This head can only be used on 1992-and-newer LT1 and LT4 engines with the reverse coolant flow design. It makes a great starting point for you to build a high horsepower version of one of these engines.