1759VBP GEN I SBC with Vortec Bypass Port y block 4L GMC K15/K1500 PICKUP 67-66

4L GMC K15/K1500 PICKUP 67-66 V8 283 4

0L Vortec gmc sierra 13-07 V8 325 5

Fan CFM Range: 500-599

1964 - 1967 Pontiac Bonneville

1L chevrolet k10/1500 pickup 79-78 V8 305 5

1759VBP GEN I SBC with Vortec Bypass Port y block 4L GMC K15/K1500 PICKUP 67-66More Power. More Heat! Flowkooler pump 1759VBP is designed for Gen I SBCs with Vortec heads. Unlike internal bypass passages found in older blocks the Vortec blocks and heads do not have the internal bypass passages so the the coolant bypass is an external hose connection from the water pump to the intake manifold. You run a bypass hose from a bung on the top rear of the water pump to a matching threaded port on the intake manifold to ensure