Holley 300-290 - Holley Single Plane EFI Split-Design Race Intake Manifold- GM LS3/L92

The new Holley Single-Plane Race intake manifold were designed with performance in mind. They feature a race bred, two piece split feature that was previously only found on the most expensive race intakes. The manifold will fit GM LS Gen III engines with LS3/L92 heads and are intended for 4150 style square bore flanged carburetors or throttle body EFI.The LS Race single-plane intake manifold was designed for hi-performance/racing engine applications, 5.3 to 6.2+ liter displacement, and maximum engine speeds of 6000-7000 rpm, depending on the engine combination. This single-plane design provides optimal performance across the RPM spectrum while providing maximum performance up to 7000 rpm.The Holley LS Race manifold incorporates a split feature, which allows disassembly of the intake for direct access to internal plenum and port surfaces, making custom porting and matching a snap. With shoulder bolt locators and O-ring seal, reassembly is simple and precise.Technical Data:? A-B Height - 7.20" (0° carb flange angle)? Port Size- 2.59" Height x 1.28" Wide? Throttle Body Flange - Standard 4150 for up to 1-3/4" diameter throttle bores? As-Cast Runner Cross-Sectional Area - 4.5 in² at the runner entry tapered to 3.2 in² at the flange exit

Two different length fuel rail bracket sets are included; the long brackets are for mounting the fuel rails at a height for Bosch style EV1 type fuel injectors. The short brackets are for mounting the fuel rails at a height for GM OE LS7 fuel injectors. When using the OE GM LS7 injector, the O-ring on the outlet (intake manifold) end of the injector must be changed to the O-ring supplied in the short bracket pack.