The Edelbrock 90mm single bore throttle body is intended for Pro-Flo XT and EFI Victor Elbow applications. It has provisions for either LS1 or LS2 mounting bolt patterns. The throttle body uses LS1 style TPS and IAC. It offers better idle control than other 90mm throttle bodies, because of the addition of an idle bleed screw. By using the bleed screw to create a base amount of idle air flow instead of throttle tip-in, the TPS signal is unaffected. Polished Finish