FAST 146302B-KIT LSXR 102mm Intake Billet Throttle Body Kit for LS1/LS2/LS6

Vehicle Fitment

• GM LS-based engines: LS1, LS2, LS6 (cathedral port cylinder heads) - fitment is engine-specific, not vehicle-year specific; applicable to any chassis running these engines

Fitment Notes

• Cathedral port applications only - not compatible with rectangular port heads (LS3, LS7, L92)
• For LS7 cathedral-to-rectangular applications, FAST offers a separate kit (146202B-KIT); for LS3/L92 rectangular port applications, FAST offers 146102B-KIT
• Does not include manifold-to-cylinder-head gaskets - order separately
• Does not include fuel rails or fuel injectors
• Replacement lower shell available separately under FAST part number 146301

Features

• Complete bolt-on kit pairing the FAST LSXR 102mm polymer intake manifold with a FAST Big Mouth 102mm billet throttle body
• Billet aluminum throttle body reduces blade deflection versus cast units
• Polymer manifold construction reduces heat soak compared to aluminum manifolds
• Three-piece modular manifold design allows easy disassembly
• Removable runners permit porting and runner-specific modification
• Integrated nitrous bungs built into the manifold
• Bolt-on fitment retains factory accessory compatibility without modification
• 102mm throttle body inlet also accepts stock or aftermarket 90mm/92mm throttle bodies if preferred

Specifications

• Manufacturer Part Number: 146302B-KIT
• UPC: 036584399247
• Cylinder Head Configuration: Cathedral Port, LS1/LS2/LS6
• Manifold Material: Polymer
• Throttle Body Bore: 102mm
• Throttle Body Style: Cable driven, billet aluminum
• Includes Throttle Body: Yes
• Includes Throttle Body to Manifold Hardware: Yes
• Includes Manifold to Cylinder Head Gaskets: No
• Includes Fuel Rails: No
• Includes Fuel Injectors: No
• Package Dimensions: 28.5" x 16.37" x 9.5"
• Package Weight: 20 lbs

Included Components

• 1x LSXR 102mm Intake Manifold (upper and lower shell, polymer)
• 1x FAST Big Mouth 102mm Billet Throttle Body
• 1x Throttle body to manifold mounting hardware

Product Description

The FAST 146302B-KIT pairs the LSXR 102mm cathedral port intake manifold with FAST's Big Mouth 102mm billet throttle body in a single bolt-on package for LS1, LS2, and LS6 engines. The polymer manifold construction cuts heat soak versus aluminum alternatives, while the billet throttle body reduces blade deflection compared to a cast unit, targeting improved airflow and throttle response over a factory cathedral port setup.

Like the rest of the LSXR lineup, the manifold uses a three-piece modular design with removable runners, so builders can access individual runners for porting or tuning without replacing the entire manifold - and if a runner or the lower shell is ever damaged, FAST sells the lower shell separately (146301) rather than requiring a full manifold replacement. Integrated nitrous bungs are built in for anyone planning a nitrous setup down the line.

This is a manifold-and-throttle-body kit only: it does not include manifold-to-head gaskets, fuel rails, or injectors, so builders should plan to source those separately, and it's strictly a cathedral port piece - LS3, LS7, and L92 rectangular port engines need a different FAST kit entirely. It's best suited to LS1/LS2/LS6 owners doing a manifold upgrade who already have or are sourcing the rest of the fuel system components.