1975 GMC C25 Suburban Engine: 5.7L V8;EngineVIN: Y; FuelSystem: 4BBL; 4 Bore Gasket; Open plenum;. 1975 GMC C25 Suburban Engine: 7.4L V8; 4 Bore Gasket; Open plenum;. 1976 GMC C25 Suburban Engine: 5.7L V8;EngineVIN: L; FuelSystem: 4BBL; 4 Bore Gasket; Open plenum;.
