This little pigtail is a lifesaver. GM alternators require an exciter wire with a 12V switched source, otherwise they won't charge. We hear from a lot of swappers who have this problem,...
This is the standard LS plug with 3/8 NPT thread. This fits the standard Holley EFI harnesses (and others), and is a popular choice when installing modern EFI on an classic engine (such as SBC, small...