This is a basic 4bbl carburetor based on a 460 CFM Impco 425 mixer and spread-bore Quadrajet throttle body.  The throttle-body is NOT included in this kit and you must source it yourself.  This kit is designed to convert a Quadrajet to a Model 425 carburetor.  You assemble this carburetor from the following components:

• 1 x Impco CT425M-2 Model 425 Mixer, Silicone
• 1 x Impco AA3-86 Adapter, 425 Mixer to Rochester Q-Jet
• 1 x Gann 88EN Vapour Elbow, Nylon, 1" Hose x 1" MNPT

To make an underhood conversion kit, you must add either the BCP-EE or the BCP-EV Basic Components kits.

Propane carburetors are not oversized like gasoline carburetors.  This carburetor will properly meter fuel to a 350 CID (5.7L) engine up to 5344 RPM.  On a 454 CID (7.4L) engine, this carburetor is good to 4120 RPM.  Above these RPMS, these engines will simply gradually lose power.  For stock V8 engine applications, this carburetor will work well.

For open-loop engine applications above 390 CID (or for generally better fuel economy), we recommend replacing the air-gas valve with PN AV1-1644-2.