has anyone used a 1989 or 1990 Mark IV 454 in a project acr or truck? I have been looking at water pumps and the references say the flow is in reverse from other Mark IV(65-87) water pumps. I am wondering if that is because of the external pulley system on 1989-91 454s or is it an internal design that is different? Every other major piece fits the similar on 1965-91 Mark IV 454s it seems except the long/short water pump.
The flow is not reversed, just the direction the pump rotates. The water still comes in the bottom of the pump and is pumped into the engine through the two holes in the front of the block.
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