How to connect LS1 heater hoses to 240z heater core

[nocones]

Getting close to finishing my LS-1 swap and am trying to figure out which heater hose from the water pump goes to which heater core connection on my 73 240z.

 

I tried searching but just when I thought I found the answer in this thread (first it says that the 3/4" connection is an outlet and the 5/8" is the return)

 

http://forums.hybridz.org/showthread.php?t=118413&highlight=heater+hose

 

after reading further, someone says it runs the opposite way.

 

So, is the 3/4" line on the waterpump an inlet or outlet? Which hose does this connect to on my heater core at the firewall, the one closer to the center of the car?

 

Thanks

[nocones]

When I look at this image, it looks as though the 3/4" connection might be the return line since it is the one that is toward the front of the engine...assuming the image is accurate with respect to actual location of the inlet/outlet relative to one another.

 

 

On the Datsun heater core side I'm guessing that the inlet is the bottom one (on the firewall) that attaches to the heater valve on the side of the heater core.

 

If this logic is correct then that would mean I should connect the 5/8" line from the LS1 water pump (the one toward the rear of the car) to the bottom of the two hoses that go through the firewall.

 

Anybody care to agree or disagree?

[Dudeboy]

This visual may help you. Drop down to the second page for the LS1 info.http://www.hotrodlane.cc/PDFFILES/waterpassageLTLS.pdf

 

I am using a aftermarket heater, so you need to check out a factory manual for the flow of the 1973 240z heater, this will get you going.

 

Good luck, Glenn