Fits SB Chevy GM LS Engine. Aeroflow Performance transmission bellhousings are intended for street/strip applications. Manufactured from one-piece A356-T6 cast aluminium and specifically engineered with an open bottom to allow for converter access, reduced diameter to give you provide clearance, and a contoured flange to match the rear of your engine block. The bolt pattern for the bellhousing is designed to suit Small Block Chev or GM LS engine blocks.