PORTS AND FITTINGS
The fuel rail ports are tapped for 8AN ORB.
Appropriate fittings must be selected based on the specific application. Ample space around the fuel rail port(s) is necessary for larger accessories such as fuel pressure regulators, fuel pressure gauges, and fuel pulse dampers. To verify clearance, the dimensional drawings on the product pages can be used as a reference guide.
Manufactured with a large 0.69" internal bore, the fuel rails can support all necessary engine power requirements. They are CNC machined from extruded 6063 aluminum, black anodized, and laser etched for a high quality surface finish. All end ports are machined with 8AN ORB (3/4-16 female) threads. The lower center ports can be used for optional adapters and are also tapped with 8AN ORB (3/4-16 female) threads. For a list of 8AN ORB adapter fittings.
The kit features specifically designed billet mounts. These modular "feet" allow compatibility on the following GM LS engines by simply flipping them and reinstalling into different threaded holes on the rails: LS1, LS2, LS3, LS6, L76, L99
Like the OEM fuel rails, the injector bores are 14mm ID so factory injectors are permitted. 
These fuel rails are compatible with all fuel types including popular alcohol mixtures such as E85.
Not compatible with the factory engine cover.
INCLUDED
20-0232 GM LS Fuel Rail Kit:
-Black Anodized Laser Etched Aluminum Fuel Rails (x2)
-Black Anodized Aluminum Mounting Feet (x4)
-Stainless Steel Mounting Feet Hardware (x8)
-Stainless Steel Replacement Mounting Bolts (x4)