Hi, I was wondering if I can remove the coolant lines circled in the picture (not my car)? They look to go to the heater which I will be removing soon anyway, but are they needed to circulate the coolant properly? Thanks for the help!

Yes but you need to plug the hole at the back of the head and plug the intake at the water neck.

You are correct that these lines supply the heater. However... they also connect around the back of the engine to the carbs and then back into the block. Look a bit closer to all the plumbing before making a decision.

hmm ok, thanks for the input! I'll think it over before I completely remove it, thanks!

A quick question: You don't want a heater? How about a defroster fro the front window? Removing this coolant circuit will disable the heater/defroster.

If it's a dedicated track car, then it may make sense. If you drive anytime when it's cool, the defrost comes in kinda handy...

Yoshi, BTW, I'm just south of you in San Mateo, so if you want to get together to tinker on our Z's. just let me know.

Julio

Yoshi, FAIW, in the '77 and '78 Z, circulation to the heater core is cut off (via a pneumatic stop ****) when the system isn't in the heating mode, so I'd say circulation through this loop isn't important for proper engine cooling. For instance it's not like a Miata's heater loop, if I remember correctly, which is constantly flowing and important for proper cooling of the #4.