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SBC reverse rotation coolant line help


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Okay, first off I searched but couldn't find an answer so here it goes.

 

I picked up a 305 TBI engine out of a 1991 RS with the serpentine belt set up. I am converting it to a carb set-up, but I need to know how to set up the coolant lines properly. The water pump does not have a heater hose bung. I have an Edelbrock intake manifold with a water cross-over line at the back by the distributor, and there is a bung for a hose nipple. Do you route one heater hose from the front nipple by the thermostat to the heater core, and the other line at the back of the head to the other port on the heater core? The alternative is to just by a standard rotation pump and v-belt pulleys, but I really don't want to sink money into doing that when I have good parts to begin with.

 

Thanks in advance for any help

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The front nipple by the thermostat is the hot water out to the heater core.  For a cooler water return from the heater core, install a "T", with a 5/8" or 3/4" stub, into the lower radiator hose for the cooler water return that will get sucked into the water pump which then goes onto the block and cylinder heads for engine cooling.  Jags that Run has these "Ts" for sale.  See their Internet Site.

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Makes sense. The motor is currently set up with a heater hose nipple at the back of the head, which ran to the heater core. Would I be able to use this as the hot supply in lieu of running a hose to the front by he thermostat? I only ask because the coolant system for this car was a bit complicated in design, and looks like crap. I would like a much cleaner install if I can get close to that.

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The Small Block Chevrolet engine has the least cooling of the rear (#7 & #8 cylinders) with the least water flow.  For most effective heating of the heater core, highly recommend taking hot water from the front of the intake manifold nearest the thermostat housing.  For summer operation, a 1/4 turn ball type valve can be installed in this hot water line.  In the summer just turn the ball valve closed and this keeps the heater core COOL allowing use of fan operated venting of the cabin.  Also very effective for Air Conditioning purposes.

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