Description
EngineQuest Performance Cast Iron Cylinder Head Bare 1.840 1.5 in Valves 170 cc Intake Small Block Chevy BDD1050457 1 2 in Head Size:8 HAWHB237U625 WM302 1.200 Micro Babbitt a very 1 2 in Head The ECU requires to know when cylinder number one is firing (or preparing to fire) so it knows the sequence of the injectors coming next