I have a 489 BBC that is almost done. What is the function of the water hose that goes from the front of the intake manifold to the top of the water pump? My SBC didn't have this and ran fine. This will mainly be a street car with little strip time. Do I have to have this hooked up? What will happen if I don't? Thanks.

Thats a bypass hose, so water can flow thru the system till the thermostat opens. Im not sure if it's a must or not, I do know that engines that have either a restrictor or no thermostat at all, or that have holes drilled in the stat, sometimes dont use that hose. John

It is a must for a stock stat. I do not have the hose but I drilled (3) 3/16 holes in my thermostat to create a bypass. Your small blocks did have a bypass but you didn't know it. It's the third hole on the one side of a small block water pump.

Thanks guys. So then all I need to do is drill three 3/16 holes around my thermostat and I'll be ok? I really don't like the look of the hose from the manifold to the waterpump.

i have a stock t-stat in my 496 and this hose is hooked up but it is bent in 2 90 degree bends to get it on there not much if any water is flowing through it and i dont have any holes drilled in my t-stat